<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019efacc-1aef-7d44-8227-2505a9411589,g:108dcd3c-e35f-4cce-be4d-c2b5a029399b-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="https://xbrl.org/2023/arcrole/summation-item" xlink:type="simple" xlink:href="https://www.xbrl.org/2023/calculation-1.1.xsd#summation-item"/>
  <link:roleRef roleURI="http://rockwellmed.com/role/UNAUDITEDCONDENSEDCONSOLIDATEDBALANCESHEETS" xlink:type="simple" xlink:href="rmti-20260630.xsd#UNAUDITEDCONDENSEDCONSOLIDATEDBALANCESHEETS"/>
  <link:calculationLink xlink:role="http://rockwellmed.com/role/UNAUDITEDCONDENSEDCONSOLIDATEDBALANCESHEETS" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019efacc-1b9b-7b30-a682-b6fd1ae0e91c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrent_019efacc-1b9b-74db-9794-52013c70a5be" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019efacc-1b9b-7b30-a682-b6fd1ae0e91c" xlink:to="loc_us-gaap_AssetsCurrent_019efacc-1b9b-74db-9794-52013c70a5be" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseRightOfUseAsset_019efacc-1b9b-7870-8192-084f924a31bb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseRightOfUseAsset"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019efacc-1b9b-7b30-a682-b6fd1ae0e91c" xlink:to="loc_us-gaap_OperatingLeaseRightOfUseAsset_019efacc-1b9b-7870-8192-084f924a31bb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_019efacc-1b9b-7a24-80db-149d90efebc3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019efacc-1b9b-7b30-a682-b6fd1ae0e91c" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_019efacc-1b9b-7a24-80db-149d90efebc3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseRightOfUseAsset_019efacc-1b9b-7875-90e0-c3b6af86d70d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseRightOfUseAsset"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019efacc-1b9b-7b30-a682-b6fd1ae0e91c" xlink:to="loc_us-gaap_FinanceLeaseRightOfUseAsset_019efacc-1b9b-7875-90e0-c3b6af86d70d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsNoncurrent_019efacc-1b9b-7241-b5e0-5cd7690cc5f4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsNoncurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019efacc-1b9b-7b30-a682-b6fd1ae0e91c" xlink:to="loc_us-gaap_OtherAssetsNoncurrent_019efacc-1b9b-7241-b5e0-5cd7690cc5f4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_019efacc-1b9b-707a-b872-df38cb122a66" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019efacc-1b9b-7b30-a682-b6fd1ae0e91c" xlink:to="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_019efacc-1b9b-707a-b872-df38cb122a66" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_019efacc-1b9b-78c0-ae06-66ba5d23a9ed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Goodwill"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019efacc-1b9b-7b30-a682-b6fd1ae0e91c" xlink:to="loc_us-gaap_Goodwill_019efacc-1b9b-78c0-ae06-66ba5d23a9ed" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrent_019efacc-1b9b-7001-a22b-691894912942" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsPayableCurrent_019efacc-1b9b-7a5e-bcee-dc2e5aae4cc9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019efacc-1b9b-7001-a22b-691894912942" xlink:to="loc_us-gaap_AccountsPayableCurrent_019efacc-1b9b-7a5e-bcee-dc2e5aae4cc9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrent_019efacc-1b9b-7944-abfa-66652596ba4e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedLiabilitiesCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019efacc-1b9b-7001-a22b-691894912942" xlink:to="loc_us-gaap_AccruedLiabilitiesCurrent_019efacc-1b9b-7944-abfa-66652596ba4e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationLiabilityCurrent_019efacc-1b9b-761f-a252-da84d696af0d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationContingentConsiderationLiabilityCurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019efacc-1b9b-7001-a22b-691894912942" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationLiabilityCurrent_019efacc-1b9b-761f-a252-da84d696af0d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilityCurrent_019efacc-1b9b-71b7-b58e-98cab01e2ab1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityCurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019efacc-1b9b-7001-a22b-691894912942" xlink:to="loc_us-gaap_OperatingLeaseLiabilityCurrent_019efacc-1b9b-71b7-b58e-98cab01e2ab1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityCurrent_019efacc-1b9b-746f-9133-c9ba1fd3def8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiabilityCurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019efacc-1b9b-7001-a22b-691894912942" xlink:to="loc_us-gaap_FinanceLeaseLiabilityCurrent_019efacc-1b9b-746f-9133-c9ba1fd3def8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermBankLoansAndNotesPayable_019efacc-1b9b-77f6-8833-67c5dad6b998" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShortTermBankLoansAndNotesPayable"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019efacc-1b9b-7001-a22b-691894912942" xlink:to="loc_us-gaap_ShortTermBankLoansAndNotesPayable_019efacc-1b9b-77f6-8833-67c5dad6b998" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerRefundLiabilityCurrent_019efacc-1b9b-78c8-99b0-98e4fa03dbd9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerRefundLiabilityCurrent"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019efacc-1b9b-7001-a22b-691894912942" xlink:to="loc_us-gaap_ContractWithCustomerRefundLiabilityCurrent_019efacc-1b9b-78c8-99b0-98e4fa03dbd9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtCurrent_019efacc-1b9b-7044-b87d-1a6d624e678d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtCurrent"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019efacc-1b9b-7001-a22b-691894912942" xlink:to="loc_us-gaap_LongTermDebtCurrent_019efacc-1b9b-7044-b87d-1a6d624e678d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_019efacc-1b9b-73b2-8f5a-ff1105853d74" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrent_019efacc-1b9b-7e4d-ab28-e68ef78239bb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019efacc-1b9b-73b2-8f5a-ff1105853d74" xlink:to="loc_us-gaap_LiabilitiesCurrent_019efacc-1b9b-7e4d-ab28-e68ef78239bb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_019efacc-1b9b-7210-bdd9-5a4952410042" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019efacc-1b9b-73b2-8f5a-ff1105853d74" xlink:to="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_019efacc-1b9b-7210-bdd9-5a4952410042" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityNoncurrent_019efacc-1b9b-7c77-bfdb-fd6c85f7eea9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiabilityNoncurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019efacc-1b9b-73b2-8f5a-ff1105853d74" xlink:to="loc_us-gaap_FinanceLeaseLiabilityNoncurrent_019efacc-1b9b-7c77-bfdb-fd6c85f7eea9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_019efacc-1b9b-7a8c-89a5-459d2774810f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtNoncurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019efacc-1b9b-73b2-8f5a-ff1105853d74" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_019efacc-1b9b-7a8c-89a5-459d2774810f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019efacc-1b9b-7ae3-ac6f-91bbcfb1dd2a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockValueOutstanding_019efacc-1b9b-75cf-af99-31810d880228" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockValueOutstanding"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_019efacc-1b9b-7ae3-ac6f-91bbcfb1dd2a" xlink:to="loc_us-gaap_PreferredStockValueOutstanding_019efacc-1b9b-75cf-af99-31810d880228" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockValueOutstanding_019efacc-1b9b-7945-9d13-7bddbcbfe927" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockValueOutstanding"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_019efacc-1b9b-7ae3-ac6f-91bbcfb1dd2a" xlink:to="loc_us-gaap_CommonStockValueOutstanding_019efacc-1b9b-7945-9d13-7bddbcbfe927" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapital_019efacc-1b9b-7c89-8894-fc6f40ee830f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapital"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_019efacc-1b9b-7ae3-ac6f-91bbcfb1dd2a" xlink:to="loc_us-gaap_AdditionalPaidInCapital_019efacc-1b9b-7c89-8894-fc6f40ee830f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_019efacc-1b9b-7cbc-8c14-af9f4cef2aee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsAccumulatedDeficit"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_019efacc-1b9b-7ae3-ac6f-91bbcfb1dd2a" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_019efacc-1b9b-7cbc-8c14-af9f4cef2aee" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_019efacc-1b9b-7d1f-b077-3ddfe9a9967b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_019efacc-1b9b-7ae3-ac6f-91bbcfb1dd2a" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_019efacc-1b9b-7d1f-b077-3ddfe9a9967b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_019efacc-1b9b-7300-926b-be82869327a2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_019efacc-1b9b-75eb-a8cb-4ed0a97f803c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_019efacc-1b9b-7300-926b-be82869327a2" xlink:to="loc_us-gaap_Liabilities_019efacc-1b9b-75eb-a8cb-4ed0a97f803c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019efacc-1b9b-7fcd-9dbf-38776282e783" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_019efacc-1b9b-7300-926b-be82869327a2" xlink:to="loc_us-gaap_StockholdersEquity_019efacc-1b9b-7fcd-9dbf-38776282e783" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommitmentsAndContingencies_019efacc-1b9b-7b03-8d26-0f556576785b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommitmentsAndContingencies"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_019efacc-1b9b-7300-926b-be82869327a2" xlink:to="loc_us-gaap_CommitmentsAndContingencies_019efacc-1b9b-7b03-8d26-0f556576785b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrent_019efacc-1b9b-792a-8a5e-4671d3671354" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019efacc-1b9b-75e2-8739-62621e4f9dbc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019efacc-1b9b-792a-8a5e-4671d3671354" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019efacc-1b9b-75e2-8739-62621e4f9dbc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterestCurrent_019efacc-1b9b-7c87-8970-27b8208ec663" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterestCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019efacc-1b9b-792a-8a5e-4671d3671354" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterestCurrent_019efacc-1b9b-7c87-8970-27b8208ec663" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_019efacc-1b9b-7add-9996-d055a3a2dea7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableNetCurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019efacc-1b9b-792a-8a5e-4671d3671354" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_019efacc-1b9b-7add-9996-d055a3a2dea7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryNet_019efacc-1b9b-7e65-bc1c-bafe49f1df59" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryNet"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019efacc-1b9b-792a-8a5e-4671d3671354" xlink:to="loc_us-gaap_InventoryNet_019efacc-1b9b-7e65-bc1c-bafe49f1df59" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_019efacc-1b9b-7704-8345-75a39c42303d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019efacc-1b9b-792a-8a5e-4671d3671354" xlink:to="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_019efacc-1b9b-7704-8345-75a39c42303d" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://rockwellmed.com/role/UNAUDITEDCONDENSEDCONSOLIDATEDSTATEMENTSOFOPERATIONS" xlink:type="simple" xlink:href="rmti-20260630.xsd#UNAUDITEDCONDENSEDCONSOLIDATEDSTATEMENTSOFOPERATIONS"/>
  <link:calculationLink xlink:role="http://rockwellmed.com/role/UNAUDITEDCONDENSEDCONSOLIDATEDSTATEMENTSOFOPERATIONS" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_019efacc-1b9b-7657-a401-c202afaba6f7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseNonoperating_019efacc-1b9b-7690-8c66-a33759411bd7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseNonoperating"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OtherNonoperatingIncomeExpense_019efacc-1b9b-7657-a401-c202afaba6f7" xlink:to="loc_us-gaap_InterestExpenseNonoperating_019efacc-1b9b-7690-8c66-a33759411bd7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeNet_019efacc-1b9b-73e0-a621-2c7012da24f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIncomeNet"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OtherNonoperatingIncomeExpense_019efacc-1b9b-7657-a401-c202afaba6f7" xlink:to="loc_us-gaap_InvestmentIncomeNet_019efacc-1b9b-73e0-a621-2c7012da24f8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss_019efacc-1b9b-779a-8485-3af2a95f2393" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OtherNonoperatingIncomeExpense_019efacc-1b9b-7657-a401-c202afaba6f7" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss_019efacc-1b9b-779a-8485-3af2a95f2393" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_019efacc-1b9b-7d7c-a982-88179aa847a3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfit_019efacc-1b9b-77eb-9ea6-d4d69679b32e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GrossProfit"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_019efacc-1b9b-7d7c-a982-88179aa847a3" xlink:to="loc_us-gaap_GrossProfit_019efacc-1b9b-77eb-9ea6-d4d69679b32e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingAndMarketingExpense_019efacc-1b9b-79d7-8a10-4e74f2a0d6f0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SellingAndMarketingExpense"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_019efacc-1b9b-7d7c-a982-88179aa847a3" xlink:to="loc_us-gaap_SellingAndMarketingExpense_019efacc-1b9b-79d7-8a10-4e74f2a0d6f0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_019efacc-1b9b-7567-9f1f-a8d3b26855cb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeneralAndAdministrativeExpense"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_019efacc-1b9b-7d7c-a982-88179aa847a3" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_019efacc-1b9b-7567-9f1f-a8d3b26855cb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpense_019fec90-878e-7f1a-9545-b453be4957bc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResearchAndDevelopmentExpense"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_019efacc-1b9b-7d7c-a982-88179aa847a3" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpense_019fec90-878e-7f1a-9545-b453be4957bc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfit_019efacc-1b9b-7acc-a624-1bb43a41d28c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GrossProfit"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_019efacc-1b9b-7ea5-8cfe-308111628ef2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_GrossProfit_019efacc-1b9b-7acc-a624-1bb43a41d28c" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_019efacc-1b9b-7ea5-8cfe-308111628ef2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_019efacc-1b9b-7b9f-b70c-e0a92c3d54b9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfGoodsAndServicesSold"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_GrossProfit_019efacc-1b9b-7acc-a624-1bb43a41d28c" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_019efacc-1b9b-7b9f-b70c-e0a92c3d54b9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019efacc-1b9b-7351-b75f-73d47a5c7083" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_019efacc-1b9b-7391-a9d8-e17133ab8193" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_019efacc-1b9b-7351-b75f-73d47a5c7083" xlink:to="loc_us-gaap_OperatingIncomeLoss_019efacc-1b9b-7391-a9d8-e17133ab8193" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_019efacc-1b9b-7ed8-bd32-9dae5736d2a2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_019efacc-1b9b-7351-b75f-73d47a5c7083" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_019efacc-1b9b-7ed8-bd32-9dae5736d2a2" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://rockwellmed.com/role/UNAUDITEDCONDENSEDCONSOLIDATEDSTATEMENTSOFCOMPREHENSIVELOSS" xlink:type="simple" xlink:href="rmti-20260630.xsd#UNAUDITEDCONDENSEDCONSOLIDATEDSTATEMENTSOFCOMPREHENSIVELOSS"/>
  <link:calculationLink xlink:role="http://rockwellmed.com/role/UNAUDITEDCONDENSEDCONSOLIDATEDSTATEMENTSOFCOMPREHENSIVELOSS" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax_019efacc-1b9b-7405-9fa1-3e82c0fa10ec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComprehensiveIncomeNetOfTax"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019efacc-1b9b-7f0e-a251-89681b97ba1b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_019efacc-1b9b-7405-9fa1-3e82c0fa10ec" xlink:to="loc_us-gaap_NetIncomeLoss_019efacc-1b9b-7f0e-a251-89681b97ba1b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax_019efacc-1b9b-79d8-8c0c-287a4015b0b4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_019efacc-1b9b-7405-9fa1-3e82c0fa10ec" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax_019efacc-1b9b-79d8-8c0c-287a4015b0b4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_019efacc-1b9b-74a0-ae44-d86e56fc6389" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_019efacc-1b9b-7405-9fa1-3e82c0fa10ec" xlink:to="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_019efacc-1b9b-74a0-ae44-d86e56fc6389" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://rockwellmed.com/role/UNAUDITEDCONDENSEDCONSOLIDATEDSTATEMENTSOFCASHFLOWS" xlink:type="simple" xlink:href="rmti-20260630.xsd#UNAUDITEDCONDENSEDCONSOLIDATEDSTATEMENTSOFCASHFLOWS"/>
  <link:calculationLink xlink:role="http://rockwellmed.com/role/UNAUDITEDCONDENSEDCONSOLIDATEDSTATEMENTSOFCASHFLOWS" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019efacc-1b9b-738b-812e-dcc117ab3f91" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireProductiveAssets_019efacc-1c49-7563-a129-4f8fe77fb502" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquireProductiveAssets"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019efacc-1b9b-738b-812e-dcc117ab3f91" xlink:to="loc_us-gaap_PaymentsToAcquireProductiveAssets_019efacc-1c49-7563-a129-4f8fe77fb502" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_019efacc-1c49-7f35-b3c1-5b16f42a17f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019efacc-1b9b-738b-812e-dcc117ab3f91" xlink:to="loc_us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_019efacc-1c49-7f35-b3c1-5b16f42a17f8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt_019efacc-1c49-778d-8529-a33582ab13e1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019efacc-1b9b-738b-812e-dcc117ab3f91" xlink:to="loc_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt_019efacc-1c49-778d-8529-a33582ab13e1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_019efacc-1c49-7121-ae8b-5400f2ba59c2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019efacc-1b9b-738b-812e-dcc117ab3f91" xlink:to="loc_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_019efacc-1c49-7121-ae8b-5400f2ba59c2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7ad4-bf47-97376a941782" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019efacc-1c49-7ae3-be38-c77d5184d196" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7ad4-bf47-97376a941782" xlink:to="loc_us-gaap_NetIncomeLoss_019efacc-1c49-7ae3-be38-c77d5184d196" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_019efacc-1c49-7f95-a8a5-4b002a9d4492" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7ad4-bf47-97376a941782" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_019efacc-1c49-7f95-a8a5-4b002a9d4492" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_019efacc-1c49-709b-ab52-4b2d15b569b1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensation"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7ad4-bf47-97376a941782" xlink:to="loc_us-gaap_ShareBasedCompensation_019efacc-1c49-709b-ab52-4b2d15b569b1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_rmti_OperatingAndFinanceLeaseRightOfUseAssetAmortizationExpense_019efacc-1c49-732d-83a1-b2f39c6fcae1" xlink:href="rmti-20260630.xsd#rmti_OperatingAndFinanceLeaseRightOfUseAssetAmortizationExpense"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7ad4-bf47-97376a941782" xlink:to="loc_rmti_OperatingAndFinanceLeaseRightOfUseAssetAmortizationExpense_019efacc-1c49-732d-83a1-b2f39c6fcae1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_019efacc-1c49-77ae-87c5-5efd668ba39d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AmortizationOfFinancingCostsAndDiscounts"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7ad4-bf47-97376a941782" xlink:to="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_019efacc-1c49-77ae-87c5-5efd668ba39d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss_019efacc-1c49-7933-81ba-e1b886247045" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss"/>
    <link:calculationArc order="6" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7ad4-bf47-97376a941782" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss_019efacc-1c49-7933-81ba-e1b886247045" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_019efacc-1c49-75f9-8d66-b39f059dabfe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable"/>
    <link:calculationArc order="7" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7ad4-bf47-97376a941782" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_019efacc-1c49-75f9-8d66-b39f059dabfe" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInInventories_019efacc-1c49-758c-90e8-72e1e3ac8659" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInInventories"/>
    <link:calculationArc order="8" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7ad4-bf47-97376a941782" xlink:to="loc_us-gaap_IncreaseDecreaseInInventories_019efacc-1c49-758c-90e8-72e1e3ac8659" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_019efacc-1c49-785e-9b37-0e3cb946f3e9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets"/>
    <link:calculationArc order="9" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7ad4-bf47-97376a941782" xlink:to="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_019efacc-1c49-785e-9b37-0e3cb946f3e9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayable_019efacc-1c49-72ac-a87e-ac9d37ec56fb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccountsPayable"/>
    <link:calculationArc order="10" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7ad4-bf47-97376a941782" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsPayable_019efacc-1c49-72ac-a87e-ac9d37ec56fb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOperatingLeaseLiability_019efacc-1c49-7b20-8649-0d6b1aac38fc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOperatingLeaseLiability"/>
    <link:calculationArc order="11" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7ad4-bf47-97376a941782" xlink:to="loc_us-gaap_IncreaseDecreaseInOperatingLeaseLiability_019efacc-1c49-7b20-8649-0d6b1aac38fc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingLiabilities_019efacc-1c49-70d0-8e8f-2fe699048ba9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOtherOperatingLiabilities"/>
    <link:calculationArc order="12" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7ad4-bf47-97376a941782" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherOperatingLiabilities_019efacc-1c49-70d0-8e8f-2fe699048ba9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInContractWithCustomerLiability_019efacc-1c49-7c8e-a74d-69fd287a5919" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInContractWithCustomerLiability"/>
    <link:calculationArc order="13" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7ad4-bf47-97376a941782" xlink:to="loc_us-gaap_IncreaseDecreaseInContractWithCustomerLiability_019efacc-1c49-7c8e-a74d-69fd287a5919" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryWriteDown_019efacc-1c49-7d60-a0b2-9b770e86c003" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryWriteDown"/>
    <link:calculationArc order="14" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7ad4-bf47-97376a941782" xlink:to="loc_us-gaap_InventoryWriteDown_019efacc-1c49-7d60-a0b2-9b770e86c003" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnDispositionOfAssets1_019efacc-1c49-7a13-a486-d2d122dcc236" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnDispositionOfAssets1"/>
    <link:calculationArc order="15" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7ad4-bf47-97376a941782" xlink:to="loc_us-gaap_GainLossOnDispositionOfAssets1_019efacc-1c49-7a13-a486-d2d122dcc236" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProvisionForDoubtfulAccounts_019fec24-8ba8-7f5b-b360-08c9e2816411" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProvisionForDoubtfulAccounts"/>
    <link:calculationArc order="16" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7ad4-bf47-97376a941782" xlink:to="loc_us-gaap_ProvisionForDoubtfulAccounts_019fec24-8ba8-7f5b-b360-08c9e2816411" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019efacc-1c49-770c-bf0d-fe28e2e5c431" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7b5c-993a-74d5f0e94997" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019efacc-1c49-770c-bf0d-fe28e2e5c431" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019efacc-1c49-7b5c-993a-74d5f0e94997" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019efacc-1c49-72f0-8fb1-03f5c382619e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019efacc-1c49-770c-bf0d-fe28e2e5c431" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019efacc-1c49-72f0-8fb1-03f5c382619e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019efacc-1c49-7383-b4af-d559da351846" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019efacc-1c49-770c-bf0d-fe28e2e5c431" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019efacc-1c49-7383-b4af-d559da351846" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019efacc-1b9b-7c81-9165-349e53c8d954" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_rmti_PaymentForAssetAcquisitionDeferredConsideration_019efacc-1b9b-7643-89de-6136c5d09d1f" xlink:href="rmti-20260630.xsd#rmti_PaymentForAssetAcquisitionDeferredConsideration"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019efacc-1b9b-7c81-9165-349e53c8d954" xlink:to="loc_rmti_PaymentForAssetAcquisitionDeferredConsideration_019efacc-1b9b-7643-89de-6136c5d09d1f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepaymentsOfNotesPayable_019efacc-1b9b-7658-93ee-c84f5018fc9c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepaymentsOfNotesPayable"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019efacc-1b9b-7c81-9165-349e53c8d954" xlink:to="loc_us-gaap_RepaymentsOfNotesPayable_019efacc-1b9b-7658-93ee-c84f5018fc9c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeasePrincipalPayments_019efacc-1b9b-7e9a-b198-8ba685dae341" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeasePrincipalPayments"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019efacc-1b9b-7c81-9165-349e53c8d954" xlink:to="loc_us-gaap_FinanceLeasePrincipalPayments_019efacc-1b9b-7e9a-b198-8ba685dae341" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://rockwellmed.com/role/IntangibleAssetsandDeferredConsiderationScheduleofIntangibleAssetsDetails" xlink:type="simple" xlink:href="rmti-20260630.xsd#IntangibleAssetsandDeferredConsiderationScheduleofIntangibleAssetsDetails"/>
  <link:calculationLink xlink:role="http://rockwellmed.com/role/IntangibleAssetsandDeferredConsiderationScheduleofIntangibleAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019efacc-1c49-775c-a0ec-efb7981d86af" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_019efacc-1c49-739e-a7ac-a8f360ee2734" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019efacc-1c49-775c-a0ec-efb7981d86af" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_019efacc-1c49-739e-a7ac-a8f360ee2734" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_019efacc-1c49-7443-9f83-6a909f4079a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019efacc-1c49-775c-a0ec-efb7981d86af" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_019efacc-1c49-7443-9f83-6a909f4079a7" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://rockwellmed.com/role/IntangibleAssetsandDeferredConsiderationScheduleofFutureAmortizationExpenseDetails" xlink:type="simple" xlink:href="rmti-20260630.xsd#IntangibleAssetsandDeferredConsiderationScheduleofFutureAmortizationExpenseDetails"/>
  <link:calculationLink xlink:role="http://rockwellmed.com/role/IntangibleAssetsandDeferredConsiderationScheduleofFutureAmortizationExpenseDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019efacc-1c49-7643-9ba9-d21c574a3539" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_019efacc-1c49-7c6b-9723-a99c1ade7755" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019efacc-1c49-7643-9ba9-d21c574a3539" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_019efacc-1c49-7c6b-9723-a99c1ade7755" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_rmti_FiniteLivedIntangibleAssetExpectedAmortizationAfterYearFour_019efacc-1c49-7ada-a446-14c38dc203ec" xlink:href="rmti-20260630.xsd#rmti_FiniteLivedIntangibleAssetExpectedAmortizationAfterYearFour"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019efacc-1c49-7643-9ba9-d21c574a3539" xlink:to="loc_rmti_FiniteLivedIntangibleAssetExpectedAmortizationAfterYearFour_019efacc-1c49-7ada-a446-14c38dc203ec" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_019efacc-1c49-7ad8-a83f-b2b9fdae507a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019efacc-1c49-7643-9ba9-d21c574a3539" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_019efacc-1c49-7ad8-a83f-b2b9fdae507a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_019efacc-1c49-7d3e-ac58-72c59426278c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019efacc-1c49-7643-9ba9-d21c574a3539" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_019efacc-1c49-7d3e-ac58-72c59426278c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_019efacc-1c49-7b1f-ad36-2b47f41a049d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019efacc-1c49-7643-9ba9-d21c574a3539" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_019efacc-1c49-7b1f-ad36-2b47f41a049d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_019efacc-1c49-78ae-acf4-132fe60c3a02" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019efacc-1c49-7643-9ba9-d21c574a3539" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_019efacc-1c49-78ae-acf4-132fe60c3a02" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://rockwellmed.com/role/InvestmentsAvailableforSaleScheduleofInvestmentsAvailableforSaleDetails" xlink:type="simple" xlink:href="rmti-20260630.xsd#InvestmentsAvailableforSaleScheduleofInvestmentsAvailableforSaleDetails"/>
  <link:calculationLink xlink:role="http://rockwellmed.com/role/InvestmentsAvailableforSaleScheduleofInvestmentsAvailableforSaleDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_019efacc-1c49-7f3b-8f21-2e7130fa3a8b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_019efacc-1c49-76ee-942a-b5e14baa2357" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_019efacc-1c49-7f3b-8f21-2e7130fa3a8b" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_019efacc-1c49-76ee-942a-b5e14baa2357" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019efacc-1c49-757a-afc7-9d65619e418a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_019efacc-1c49-7f3b-8f21-2e7130fa3a8b" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019efacc-1c49-757a-afc7-9d65619e418a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_019efacc-1c49-7da2-9760-8c52fe82ec2e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_019efacc-1c49-7f3b-8f21-2e7130fa3a8b" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_019efacc-1c49-7da2-9760-8c52fe82ec2e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss_019efacc-1c49-7578-80e4-7d3ad8aee04b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_019efacc-1c49-7f3b-8f21-2e7130fa3a8b" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss_019efacc-1c49-7578-80e4-7d3ad8aee04b" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://rockwellmed.com/role/SegmentReportingDetails" xlink:type="simple" xlink:href="rmti-20260630.xsd#SegmentReportingDetails"/>
  <link:calculationLink xlink:role="http://rockwellmed.com/role/SegmentReportingDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_019efacc-1c49-7ad2-8bbc-6a78e46f686f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfit_019efacc-1c49-7359-a563-7b5896cf00f0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GrossProfit"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_019efacc-1c49-7ad2-8bbc-6a78e46f686f" xlink:to="loc_us-gaap_GrossProfit_019efacc-1c49-7359-a563-7b5896cf00f0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LaborAndRelatedExpense_019efacc-1c49-713f-9cef-15473189d6ce" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LaborAndRelatedExpense"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_019efacc-1c49-7ad2-8bbc-6a78e46f686f" xlink:to="loc_us-gaap_LaborAndRelatedExpense_019efacc-1c49-713f-9cef-15473189d6ce" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_rmti_AdministrativeCosts_019efacc-1c49-7d0f-b183-8e65a5c0e452" xlink:href="rmti-20260630.xsd#rmti_AdministrativeCosts"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_019efacc-1c49-7ad2-8bbc-6a78e46f686f" xlink:to="loc_rmti_AdministrativeCosts_019efacc-1c49-7d0f-b183-8e65a5c0e452" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://rockwellmed.com/role/InventoryScheduleofComponentsofInventoryDetails" xlink:type="simple" xlink:href="rmti-20260630.xsd#InventoryScheduleofComponentsofInventoryDetails"/>
  <link:calculationLink xlink:role="http://rockwellmed.com/role/InventoryScheduleofComponentsofInventoryDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryNet_019efacc-1c49-7622-9055-850b761149f5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryWorkInProcessNetOfReserves_019efacc-1c49-7ad6-a395-34cbbaff1aa1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryWorkInProcessNetOfReserves"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_InventoryNet_019efacc-1c49-7622-9055-850b761149f5" xlink:to="loc_us-gaap_InventoryWorkInProcessNetOfReserves_019efacc-1c49-7ad6-a395-34cbbaff1aa1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryRawMaterialsNetOfReserves_019efacc-1c49-77e7-90f6-898981e4c1c1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryRawMaterialsNetOfReserves"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_InventoryNet_019efacc-1c49-7622-9055-850b761149f5" xlink:to="loc_us-gaap_InventoryRawMaterialsNetOfReserves_019efacc-1c49-77e7-90f6-898981e4c1c1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryFinishedGoodsNetOfReserves_019efacc-1c49-75c4-9ca7-00ddac0cff13" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryFinishedGoodsNetOfReserves"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_InventoryNet_019efacc-1c49-7622-9055-850b761149f5" xlink:to="loc_us-gaap_InventoryFinishedGoodsNetOfReserves_019efacc-1c49-75c4-9ca7-00ddac0cff13" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://rockwellmed.com/role/PropertyandEquipmentScheduleofMajorClassesofPropertyandEquipmentDetails" xlink:type="simple" xlink:href="rmti-20260630.xsd#PropertyandEquipmentScheduleofMajorClassesofPropertyandEquipmentDetails"/>
  <link:calculationLink xlink:role="http://rockwellmed.com/role/PropertyandEquipmentScheduleofMajorClassesofPropertyandEquipmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_019efacc-1c49-740e-8c98-898c1456b0a2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_019efacc-1c49-7479-a811-23ab50a9718b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNet_019efacc-1c49-740e-8c98-898c1456b0a2" xlink:to="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_019efacc-1c49-7479-a811-23ab50a9718b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross_019efacc-1c49-7e14-b37f-ade38debc1f2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentGross"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNet_019efacc-1c49-740e-8c98-898c1456b0a2" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentGross_019efacc-1c49-7e14-b37f-ade38debc1f2" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://rockwellmed.com/role/AccruedLiabilitiesDetails" xlink:type="simple" xlink:href="rmti-20260630.xsd#AccruedLiabilitiesDetails"/>
  <link:calculationLink xlink:role="http://rockwellmed.com/role/AccruedLiabilitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrent_019efacc-1c49-75ea-ade5-cc722aa770ea" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedLiabilitiesCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAccruedLiabilitiesCurrent_019efacc-1c49-7405-8974-1c4261da74e7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAccruedLiabilitiesCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019efacc-1c49-75ea-ade5-cc722aa770ea" xlink:to="loc_us-gaap_OtherAccruedLiabilitiesCurrent_019efacc-1c49-7405-8974-1c4261da74e7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WorkersCompensationLiabilityCurrent_019efacc-1c49-713d-81d0-b6698ad8c677" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WorkersCompensationLiabilityCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019efacc-1c49-75ea-ade5-cc722aa770ea" xlink:to="loc_us-gaap_WorkersCompensationLiabilityCurrent_019efacc-1c49-713d-81d0-b6698ad8c677" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_rmti_AccruedUnvoucheredReceiptsCurrent_019efacc-1c49-76a3-829a-40db0b0dea89" xlink:href="rmti-20260630.xsd#rmti_AccruedUnvoucheredReceiptsCurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019efacc-1c49-75ea-ade5-cc722aa770ea" xlink:to="loc_rmti_AccruedUnvoucheredReceiptsCurrent_019efacc-1c49-76a3-829a-40db0b0dea89" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_019efacc-1c49-7abf-a438-6e9e8f7d05ac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeRelatedLiabilitiesCurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019efacc-1c49-75ea-ade5-cc722aa770ea" xlink:to="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_019efacc-1c49-7abf-a438-6e9e8f7d05ac" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://rockwellmed.com/role/StockholdersEquityScheduleofCommonStockReservedforIssuanceDetails" xlink:type="simple" xlink:href="rmti-20260630.xsd#StockholdersEquityScheduleofCommonStockReservedforIssuanceDetails"/>
  <link:calculationLink xlink:role="http://rockwellmed.com/role/StockholdersEquityScheduleofCommonStockReservedforIssuanceDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_019efacc-1c49-733a-b907-37c310170447" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockCapitalSharesReservedForFutureIssuance"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019efacc-1c49-7025-947a-01ee6f2ce464" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_019efacc-1c49-733a-b907-37c310170447" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019efacc-1c49-7025-947a-01ee6f2ce464" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertiblePreferredStockSharesReservedForFutureIssuance_019efacc-1c49-78db-bffa-507f228b17bb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConvertiblePreferredStockSharesReservedForFutureIssuance"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_019efacc-1c49-733a-b907-37c310170447" xlink:to="loc_us-gaap_ConvertiblePreferredStockSharesReservedForFutureIssuance_019efacc-1c49-78db-bffa-507f228b17bb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightOutstanding_019efacc-1c49-7c3c-a752-73d4611c27c5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightOutstanding"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_019efacc-1c49-733a-b907-37c310170447" xlink:to="loc_us-gaap_ClassOfWarrantOrRightOutstanding_019efacc-1c49-7c3c-a752-73d4611c27c5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_019efacc-1c49-7a8c-8759-1d4b9c3d6fa0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_019efacc-1c49-733a-b907-37c310170447" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_019efacc-1c49-7a8c-8759-1d4b9c3d6fa0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_019efacc-1c49-7c2a-bbc3-d915bdd33b14" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_019efacc-1c49-733a-b907-37c310170447" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_019efacc-1c49-7c2a-bbc3-d915bdd33b14" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://rockwellmed.com/role/LeasesScheduleofLeaseCostsDetails" xlink:type="simple" xlink:href="rmti-20260630.xsd#LeasesScheduleofLeaseCostsDetails"/>
  <link:calculationLink xlink:role="http://rockwellmed.com/role/LeasesScheduleofLeaseCostsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_rmti_FinanceLeaseExpense_019efacc-1c49-750d-9e4d-a98c3a256bbf" xlink:href="rmti-20260630.xsd#rmti_FinanceLeaseExpense"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseInterestExpense_019efacc-1c49-79f4-b1ce-89526397c259" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseInterestExpense"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_rmti_FinanceLeaseExpense_019efacc-1c49-750d-9e4d-a98c3a256bbf" xlink:to="loc_us-gaap_FinanceLeaseInterestExpense_019efacc-1c49-79f4-b1ce-89526397c259" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseRightOfUseAssetAmortization_019efacc-1c49-75bd-9c6e-633ede04a6c7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseRightOfUseAssetAmortization"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_rmti_FinanceLeaseExpense_019efacc-1c49-750d-9e4d-a98c3a256bbf" xlink:to="loc_us-gaap_FinanceLeaseRightOfUseAssetAmortization_019efacc-1c49-75bd-9c6e-633ede04a6c7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LeaseCost_019efacc-1c49-7dca-9c95-25d6b5795886" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LeaseCost"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseCost_019efacc-1c49-778a-a4d9-fe5f73ddcbe9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseCost"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LeaseCost_019efacc-1c49-7dca-9c95-25d6b5795886" xlink:to="loc_us-gaap_OperatingLeaseCost_019efacc-1c49-778a-a4d9-fe5f73ddcbe9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_rmti_FinanceLeaseExpense_019efacc-1c49-704a-9096-fd29f8a0e599" xlink:href="rmti-20260630.xsd#rmti_FinanceLeaseExpense"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LeaseCost_019efacc-1c49-7dca-9c95-25d6b5795886" xlink:to="loc_rmti_FinanceLeaseExpense_019efacc-1c49-704a-9096-fd29f8a0e599" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermLeaseCost_019efacc-1c49-75a8-9596-525716594754" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShortTermLeaseCost"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LeaseCost_019efacc-1c49-7dca-9c95-25d6b5795886" xlink:to="loc_us-gaap_ShortTermLeaseCost_019efacc-1c49-75a8-9596-525716594754" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://rockwellmed.com/role/LeasesScheduleofFinanceLeaseandOperatingLeaseMaturitiesDetails" xlink:type="simple" xlink:href="rmti-20260630.xsd#LeasesScheduleofFinanceLeaseandOperatingLeaseMaturitiesDetails"/>
  <link:calculationLink xlink:role="http://rockwellmed.com/role/LeasesScheduleofFinanceLeaseandOperatingLeaseMaturitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_019efacc-1c49-7ea7-8806-e9116be5b2c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_019efacc-1c49-75ba-830f-660989015b80" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_019efacc-1c49-7ea7-8806-e9116be5b2c6" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_019efacc-1c49-75ba-830f-660989015b80" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_019efacc-1c49-7301-b9e2-cd9ae3c70c10" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_019efacc-1c49-7ea7-8806-e9116be5b2c6" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_019efacc-1c49-7301-b9e2-cd9ae3c70c10" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_019efacc-1c49-72ab-8100-76c2fd5762f5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_019efacc-1c49-7ea7-8806-e9116be5b2c6" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_019efacc-1c49-72ab-8100-76c2fd5762f5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_019efacc-1c49-7ee1-a5a4-48a510755873" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_019efacc-1c49-7ea7-8806-e9116be5b2c6" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_019efacc-1c49-7ee1-a5a4-48a510755873" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_019efacc-1c49-766a-937b-a234160f392a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_019efacc-1c49-7ea7-8806-e9116be5b2c6" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_019efacc-1c49-766a-937b-a234160f392a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_rmti_LesseeOperatingLeaseLiabilityToBePaidAfterYearFour_019efacc-1c49-7246-9738-a6500dcbc8c6" xlink:href="rmti-20260630.xsd#rmti_LesseeOperatingLeaseLiabilityToBePaidAfterYearFour"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_019efacc-1c49-7ea7-8806-e9116be5b2c6" xlink:to="loc_rmti_LesseeOperatingLeaseLiabilityToBePaidAfterYearFour_019efacc-1c49-7246-9738-a6500dcbc8c6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_019efacc-1c49-7b10-b41c-f277cc507984" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiabilityPaymentsDue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiability_019efacc-1c49-7fd8-8257-8aeb2e19a3ee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiability"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_019efacc-1c49-7b10-b41c-f277cc507984" xlink:to="loc_us-gaap_FinanceLeaseLiability_019efacc-1c49-7fd8-8257-8aeb2e19a3ee" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityUndiscountedExcessAmount_019efacc-1c49-7499-93b6-d2f67600c763" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiabilityUndiscountedExcessAmount"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_019efacc-1c49-7b10-b41c-f277cc507984" xlink:to="loc_us-gaap_FinanceLeaseLiabilityUndiscountedExcessAmount_019efacc-1c49-7499-93b6-d2f67600c763" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://rockwellmed.com/role/LeasesScheduleofFinanceLeaseandOperatingLeaseMaturitiesDetails_1" xlink:type="simple" xlink:href="rmti-20260630.xsd#LeasesScheduleofFinanceLeaseandOperatingLeaseMaturitiesDetails_1"/>
  <link:calculationLink xlink:role="http://rockwellmed.com/role/LeasesScheduleofFinanceLeaseandOperatingLeaseMaturitiesDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_019efacc-1c49-72b0-87d9-4fc175a1364c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_019efacc-1c49-702e-b3b5-52deb072e5c1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_019efacc-1c49-72b0-87d9-4fc175a1364c" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_019efacc-1c49-702e-b3b5-52deb072e5c1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiability_019efacc-1c49-7e71-aab8-1322ee015c83" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiability"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_019efacc-1c49-72b0-87d9-4fc175a1364c" xlink:to="loc_us-gaap_OperatingLeaseLiability_019efacc-1c49-7e71-aab8-1322ee015c83" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_019efacc-1c49-7dcc-b2af-da3222f3720b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiabilityPaymentsDue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityPaymentsRemainderOfFiscalYear_019efacc-1c49-7ade-9c19-61ab20fa8f72" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiabilityPaymentsRemainderOfFiscalYear"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_019efacc-1c49-7dcc-b2af-da3222f3720b" xlink:to="loc_us-gaap_FinanceLeaseLiabilityPaymentsRemainderOfFiscalYear_019efacc-1c49-7ade-9c19-61ab20fa8f72" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueYearThree_019efacc-1c49-7dea-b333-b201fc1203d3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiabilityPaymentsDueYearThree"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_019efacc-1c49-7dcc-b2af-da3222f3720b" xlink:to="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueYearThree_019efacc-1c49-7dea-b333-b201fc1203d3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueNextTwelveMonths_019efacc-1c49-77b7-be3e-4bc139d993d9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiabilityPaymentsDueNextTwelveMonths"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_019efacc-1c49-7dcc-b2af-da3222f3720b" xlink:to="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueNextTwelveMonths_019efacc-1c49-77b7-be3e-4bc139d993d9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueYearTwo_019efacc-1c49-767f-b96f-8514ec1b2aad" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiabilityPaymentsDueYearTwo"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_019efacc-1c49-7dcc-b2af-da3222f3720b" xlink:to="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueYearTwo_019efacc-1c49-767f-b96f-8514ec1b2aad" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueYearFour_019efacc-1c49-737a-9af6-9519684854da" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiabilityPaymentsDueYearFour"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_019efacc-1c49-7dcc-b2af-da3222f3720b" xlink:to="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueYearFour_019efacc-1c49-737a-9af6-9519684854da" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://rockwellmed.com/role/LoanandSecurityAgreementScheduleofPrincipalPaymentsonTermLoanDetails" xlink:type="simple" xlink:href="rmti-20260630.xsd#LoanandSecurityAgreementScheduleofPrincipalPaymentsonTermLoanDetails"/>
  <link:calculationLink xlink:role="http://rockwellmed.com/role/LoanandSecurityAgreementScheduleofPrincipalPaymentsonTermLoanDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_019efacc-1c49-7649-b896-f4ac1841746a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear_019efacc-1c49-726a-b452-d05288719bac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DebtInstrumentCarryingAmount_019efacc-1c49-7649-b896-f4ac1841746a" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear_019efacc-1c49-726a-b452-d05288719bac" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_019efacc-1c49-743d-b2f7-ba3738452f05" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DebtInstrumentCarryingAmount_019efacc-1c49-7649-b896-f4ac1841746a" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_019efacc-1c49-743d-b2f7-ba3738452f05" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_019efacc-1c49-7ca8-bf4b-aa461502352e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DebtInstrumentCarryingAmount_019efacc-1c49-7649-b896-f4ac1841746a" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_019efacc-1c49-7ca8-bf4b-aa461502352e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_019efacc-1c49-74f3-9e43-4b7a310570d4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DebtInstrumentCarryingAmount_019efacc-1c49-7649-b896-f4ac1841746a" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_019efacc-1c49-74f3-9e43-4b7a310570d4" xlink:type="arc"/>
  </link:calculationLink>
</link:linkbase>
