<?xml version="1.0" encoding="US-ASCII" standalone="no"?>
    <!-- Field: Doc-Info; Name: Generator; Value: GoFiler Complete; Version: 6.5a -->
    <!-- Field: Doc-Info; Name: VendorURI; Value: https://www.novaworks.com -->
    <!-- Field: Doc-Info; Name: Status; Value: 0x00000000 -->
<link:linkbase xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrli="http://www.xbrl.org/2003/instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#Cover" roleURI="http://fdctech.com/role/Cover" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#BalanceSheets" roleURI="http://fdctech.com/role/BalanceSheets" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#BalanceSheetsParenthetical" roleURI="http://fdctech.com/role/BalanceSheetsParenthetical" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#StatementsOfOperations" roleURI="http://fdctech.com/role/StatementsOfOperations" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#StatementsOfStockholdersEquityDeficit" roleURI="http://fdctech.com/role/StatementsOfStockholdersEquityDeficit" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#StatementsOfStockholdersEquityDeficitParenthetical" roleURI="http://fdctech.com/role/StatementsOfStockholdersEquityDeficitParenthetical" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#StatementsOfCashFlows" roleURI="http://fdctech.com/role/StatementsOfCashFlows" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#BusinessDescriptionAndNatureOfOperations" roleURI="http://fdctech.com/role/BusinessDescriptionAndNatureOfOperations" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#SummaryOfSignificantAccountingPolicies" roleURI="http://fdctech.com/role/SummaryOfSignificantAccountingPolicies" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#ManagementsPlans" roleURI="http://fdctech.com/role/ManagementsPlans" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#CapitalizedSoftwareCosts" roleURI="http://fdctech.com/role/CapitalizedSoftwareCosts" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#RelatedPartyTransactions" roleURI="http://fdctech.com/role/RelatedPartyTransactions" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#LineOfCredit" roleURI="http://fdctech.com/role/LineOfCredit" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#NotesPayable" roleURI="http://fdctech.com/role/NotesPayable" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#CommitmentsAndContingencies" roleURI="http://fdctech.com/role/CommitmentsAndContingencies" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#StockholdersEquityDeficit" roleURI="http://fdctech.com/role/StockholdersEquityDeficit" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#Warrants" roleURI="http://fdctech.com/role/Warrants" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#ComprehensiveIncome" roleURI="http://fdctech.com/role/ComprehensiveIncome" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#NoncontrollingInterest" roleURI="http://fdctech.com/role/NoncontrollingInterest" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#Off-balanceSheetArrangements" roleURI="http://fdctech.com/role/Off-balanceSheetArrangements" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#SubsequentEvents" roleURI="http://fdctech.com/role/SubsequentEvents" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#SummaryOfSignificantAccountingPoliciesPolicies" roleURI="http://fdctech.com/role/SummaryOfSignificantAccountingPoliciesPolicies" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#BusinessDescriptionAndNatureOfOperationsTables" roleURI="http://fdctech.com/role/BusinessDescriptionAndNatureOfOperationsTables" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#SummaryOfSignificantAccountingPoliciesTables" roleURI="http://fdctech.com/role/SummaryOfSignificantAccountingPoliciesTables" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#StockholdersEquityDeficitTables" roleURI="http://fdctech.com/role/StockholdersEquityDeficitTables" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#ComprehensiveIncomeTables" roleURI="http://fdctech.com/role/ComprehensiveIncomeTables" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#NoncontrollingInterestTables" roleURI="http://fdctech.com/role/NoncontrollingInterestTables" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#ScheduleOfConsolidatedSubsidiariesDetails" roleURI="http://fdctech.com/role/ScheduleOfConsolidatedSubsidiariesDetails" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#BusinessDescriptionAndNatureOfOperationsDetailsNarrative" roleURI="http://fdctech.com/role/BusinessDescriptionAndNatureOfOperationsDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#ScheduleOfRestatementOfPreviouslyIssuedFinancialStatementsDetails" roleURI="http://fdctech.com/role/ScheduleOfRestatementOfPreviouslyIssuedFinancialStatementsDetails" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#ScheduleOfCashCashEquivalentsAndRestrictedCashDetails" roleURI="http://fdctech.com/role/ScheduleOfCashCashEquivalentsAndRestrictedCashDetails" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#ScheduleOfExchangeRateDetails" roleURI="http://fdctech.com/role/ScheduleOfExchangeRateDetails" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#SummaryOfSignificantAccountingPoliciesDetailsNarrative" roleURI="http://fdctech.com/role/SummaryOfSignificantAccountingPoliciesDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#ManagementsPlansDetailsNarrative" roleURI="http://fdctech.com/role/ManagementsPlansDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#CapitalizedSoftwareCostsDetailsNarrative" roleURI="http://fdctech.com/role/CapitalizedSoftwareCostsDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#RelatedPartyTransactionsDetailsNarrative" roleURI="http://fdctech.com/role/RelatedPartyTransactionsDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#LineOfCreditDetailsNarrative" roleURI="http://fdctech.com/role/LineOfCreditDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#NotesPayableDetailsNarrative" roleURI="http://fdctech.com/role/NotesPayableDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#CommitmentsAndContingenciesDetailsNarrative" roleURI="http://fdctech.com/role/CommitmentsAndContingenciesDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#StockholdersEquityDeficitDetailsNarrative" roleURI="http://fdctech.com/role/StockholdersEquityDeficitDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#ScheduleOfSeriesPreferredStockDetails" roleURI="http://fdctech.com/role/ScheduleOfSeriesPreferredStockDetails" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#ScheduleOfSeriesPreferredStockDetailsParenthetical" roleURI="http://fdctech.com/role/ScheduleOfSeriesPreferredStockDetailsParenthetical" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#ScheduleOfSeriesBPreferredStockDetails" roleURI="http://fdctech.com/role/ScheduleOfSeriesBPreferredStockDetails" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#ScheduleOfSeriesBPreferredStockDetailsParenthetical" roleURI="http://fdctech.com/role/ScheduleOfSeriesBPreferredStockDetailsParenthetical" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#WarrantsDetailsNarrative" roleURI="http://fdctech.com/role/WarrantsDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#ScheduleOfChangesInAccumulatedOtherComprehensiveIncomeDetails" roleURI="http://fdctech.com/role/ScheduleOfChangesInAccumulatedOtherComprehensiveIncomeDetails" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#ComprehensiveIncomeDetailsNarrative" roleURI="http://fdctech.com/role/ComprehensiveIncomeDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#ScheduleOfNoncontrollingInterestDetails" roleURI="http://fdctech.com/role/ScheduleOfNoncontrollingInterestDetails" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#NoncontrollingInterestDetailsNarrative" roleURI="http://fdctech.com/role/NoncontrollingInterestDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="fdct-20260331.xsd#SubsequentEventsDetailsNarrative" roleURI="http://fdctech.com/role/SubsequentEventsDetailsNarrative" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/Cover" xlink:title="00000001 - Document - Cover" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/BalanceSheets" xlink:title="00000002 - Statement - Consolidated Balance Sheets">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrent" xlink:label="loc_us-gaapAssetsCurrent" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaapCashAndCashEquivalentsAtCarryingValue" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapAssetsCurrent" xlink:to="loc_us-gaapCashAndCashEquivalentsAtCarryingValue" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCashCurrent" xlink:label="loc_us-gaapRestrictedCashCurrent" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapAssetsCurrent" xlink:to="loc_us-gaapRestrictedCashCurrent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaapAccountsReceivableNetCurrent" />
      <link:calculationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapAssetsCurrent" xlink:to="loc_us-gaapAccountsReceivableNetCurrent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrepaidExpenseCurrent" xlink:label="loc_us-gaapPrepaidExpenseCurrent" />
      <link:calculationArc order="4" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapAssetsCurrent" xlink:to="loc_us-gaapPrepaidExpenseCurrent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherReceivablesNetCurrent" xlink:label="loc_us-gaapOtherReceivablesNetCurrent" />
      <link:calculationArc order="5" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapAssetsCurrent" xlink:to="loc_us-gaapOtherReceivablesNetCurrent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets" xlink:label="loc_us-gaapAssets" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapAssets" xlink:to="loc_us-gaapAssetsCurrent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaapPropertyPlantAndEquipmentNet" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapAssets" xlink:to="loc_us-gaapPropertyPlantAndEquipmentNet" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrepaidExpenseNoncurrent" xlink:label="loc_us-gaapPrepaidExpenseNoncurrent" />
      <link:calculationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapAssets" xlink:to="loc_us-gaapPrepaidExpenseNoncurrent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="fdct-20260331.xsd#FDCT_CapitalizedSoftwareNet" xlink:label="loc_FDCTCapitalizedSoftwareNet" />
      <link:calculationArc order="4" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapAssets" xlink:to="loc_FDCTCapitalizedSoftwareNet" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures" xlink:label="loc_us-gaapInvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures" />
      <link:calculationArc order="5" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapAssets" xlink:to="loc_us-gaapInvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedInvestmentIncomeReceivable" xlink:label="loc_us-gaapAccruedInvestmentIncomeReceivable" />
      <link:calculationArc order="6" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapAssets" xlink:to="loc_us-gaapAccruedInvestmentIncomeReceivable" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="loc_us-gaapIntangibleAssetsNetExcludingGoodwill" />
      <link:calculationArc order="7" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapAssets" xlink:to="loc_us-gaapIntangibleAssetsNetExcludingGoodwill" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxesReceivableNoncurrent" xlink:label="loc_us-gaapIncomeTaxesReceivableNoncurrent" />
      <link:calculationArc order="8" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapAssets" xlink:to="loc_us-gaapIncomeTaxesReceivableNoncurrent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxesAndOtherTaxReceivableCurrent" xlink:label="loc_us-gaapDeferredIncomeTaxesAndOtherTaxReceivableCurrent" />
      <link:calculationArc order="9" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapAssets" xlink:to="loc_us-gaapDeferredIncomeTaxesAndOtherTaxReceivableCurrent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="fdct-20260331.xsd#FDCT_FairValueOfTradingPositionsForFirmProfit" xlink:label="loc_FDCTFairValueOfTradingPositionsForFirmProfit" />
      <link:calculationArc order="10" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapAssets" xlink:to="loc_FDCTFairValueOfTradingPositionsForFirmProfit" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseRightOfUseAsset" xlink:label="loc_us-gaapOperatingLeaseRightOfUseAsset" />
      <link:calculationArc order="11" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapAssets" xlink:to="loc_us-gaapOperatingLeaseRightOfUseAsset" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrent" xlink:label="loc_us-gaapLiabilitiesCurrent" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaapAccountsPayableCurrent" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapLiabilitiesCurrent" xlink:to="loc_us-gaapAccountsPayableCurrent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LinesOfCreditCurrent" xlink:label="loc_us-gaapLinesOfCreditCurrent" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapLiabilitiesCurrent" xlink:to="loc_us-gaapLinesOfCreditCurrent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedLiabilitiesCurrent" xlink:label="loc_us-gaapAccruedLiabilitiesCurrent" />
      <link:calculationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapLiabilitiesCurrent" xlink:to="loc_us-gaapAccruedLiabilitiesCurrent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="fdct-20260331.xsd#FDCT_BusinessAcquisitionLoan" xlink:label="loc_FDCTBusinessAcquisitionLoan" />
      <link:calculationArc order="4" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapLiabilitiesCurrent" xlink:to="loc_FDCTBusinessAcquisitionLoan" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="fdct-20260331.xsd#FDCT_RelatedPartyAdvances" xlink:label="loc_FDCTRelatedPartyAdvances" />
      <link:calculationArc order="5" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapLiabilitiesCurrent" xlink:to="loc_FDCTRelatedPartyAdvances" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CustomerRefundLiabilityCurrent" xlink:label="loc_us-gaapCustomerRefundLiabilityCurrent" />
      <link:calculationArc order="6" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapLiabilitiesCurrent" xlink:to="loc_us-gaapCustomerRefundLiabilityCurrent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityCurrent" xlink:label="loc_us-gaapOperatingLeaseLiabilityCurrent" />
      <link:calculationArc order="7" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapLiabilitiesCurrent" xlink:to="loc_us-gaapOperatingLeaseLiabilityCurrent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLiabilitiesCurrent" xlink:label="loc_us-gaapOtherLiabilitiesCurrent" />
      <link:calculationArc order="8" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapLiabilitiesCurrent" xlink:to="loc_us-gaapOtherLiabilitiesCurrent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaapLiabilities" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapLiabilities" xlink:to="loc_us-gaapLiabilitiesCurrent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxLiabilitiesNet" xlink:label="loc_us-gaapDeferredIncomeTaxLiabilitiesNet" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapLiabilities" xlink:to="loc_us-gaapDeferredIncomeTaxLiabilitiesNet" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermLoansPayable" xlink:label="loc_us-gaapLongTermLoansPayable" />
      <link:calculationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapLiabilities" xlink:to="loc_us-gaapLongTermLoansPayable" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent" xlink:label="loc_us-gaapOperatingLeaseLiabilityNoncurrent" />
      <link:calculationArc order="4" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapLiabilities" xlink:to="loc_us-gaapOperatingLeaseLiabilityNoncurrent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepositLiabilitiesAccruedInterest" xlink:label="loc_us-gaapDepositLiabilitiesAccruedInterest" />
      <link:calculationArc order="5" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapLiabilities" xlink:to="loc_us-gaapDepositLiabilitiesAccruedInterest" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaapStockholdersEquity" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockValue" xlink:label="loc_us-gaapPreferredStockValue" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapStockholdersEquity" xlink:to="loc_us-gaapPreferredStockValue" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaapCommonStockValue" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapStockholdersEquity" xlink:to="loc_us-gaapCommonStockValue" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="loc_us-gaapAdditionalPaidInCapital" />
      <link:calculationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapStockholdersEquity" xlink:to="loc_us-gaapAdditionalPaidInCapital" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="fdct-20260331.xsd#FDCT_SubscriptionReceivable" xlink:label="loc_FDCTSubscriptionReceivable" />
      <link:calculationArc order="4" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapStockholdersEquity" xlink:to="loc_FDCTSubscriptionReceivable" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaapAccumulatedOtherComprehensiveIncomeLossNetOfTax" />
      <link:calculationArc order="5" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapStockholdersEquity" xlink:to="loc_us-gaapAccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaapRetainedEarningsAccumulatedDeficit" />
      <link:calculationArc order="6" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapStockholdersEquity" xlink:to="loc_us-gaapRetainedEarningsAccumulatedDeficit" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:to="loc_us-gaapStockholdersEquity" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MinorityInterest" xlink:label="loc_us-gaapMinorityInterest" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:to="loc_us-gaapMinorityInterest" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaapLiabilitiesAndStockholdersEquity" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquity" xlink:to="loc_us-gaapLiabilities" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommitmentsAndContingencies" xlink:label="loc_us-gaapCommitmentsAndContingencies" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquity" xlink:to="loc_us-gaapCommitmentsAndContingencies" xlink:type="arc" weight="1" />
      <link:calculationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquity" xlink:to="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:type="arc" weight="1" />
    </link:calculationLink>
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/BalanceSheetsParenthetical" xlink:title="00000003 - Statement - Consolidated Balance Sheets (Parenthetical)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/StatementsOfOperations" xlink:title="00000004 - Statement - Consolidated Statements of Operations (Unaudited)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GrossProfit" xlink:label="loc_us-gaapGrossProfit" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapGrossProfit" xlink:to="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfGoodsAndServicesSold" xlink:label="loc_us-gaapCostOfGoodsAndServicesSold" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapGrossProfit" xlink:to="loc_us-gaapCostOfGoodsAndServicesSold" xlink:type="arc" weight="-1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingExpenses" xlink:label="loc_us-gaapOperatingExpenses" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeneralAndAdministrativeExpense" xlink:label="loc_us-gaapGeneralAndAdministrativeExpense" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapOperatingExpenses" xlink:to="loc_us-gaapGeneralAndAdministrativeExpense" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SellingAndMarketingExpense" xlink:label="loc_us-gaapSellingAndMarketingExpense" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapOperatingExpenses" xlink:to="loc_us-gaapSellingAndMarketingExpense" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Depreciation" xlink:label="loc_us-gaapDepreciation" />
      <link:calculationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapOperatingExpenses" xlink:to="loc_us-gaapDepreciation" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaapOperatingIncomeLoss" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapOperatingIncomeLoss" xlink:to="loc_us-gaapGrossProfit" xlink:type="arc" weight="1" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapOperatingIncomeLoss" xlink:to="loc_us-gaapOperatingExpenses" xlink:type="arc" weight="-1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NonoperatingIncomeExpense" xlink:label="loc_us-gaapNonoperatingIncomeExpense" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseNonoperating" xlink:label="loc_us-gaapInterestExpenseNonoperating" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNonoperatingIncomeExpense" xlink:to="loc_us-gaapInterestExpenseNonoperating" xlink:type="arc" weight="-1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNonoperatingIncomeExpense" xlink:label="loc_us-gaapOtherNonoperatingIncomeExpense" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNonoperatingIncomeExpense" xlink:to="loc_us-gaapOtherNonoperatingIncomeExpense" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:label="loc_us-gaapIncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapIncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:to="loc_us-gaapOperatingIncomeLoss" xlink:type="arc" weight="1" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapIncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:to="loc_us-gaapNonoperatingIncomeExpense" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss" xlink:label="loc_us-gaapProfitLoss" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapProfitLoss" xlink:to="loc_us-gaapIncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaapIncomeTaxExpenseBenefit" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapProfitLoss" xlink:to="loc_us-gaapIncomeTaxExpenseBenefit" xlink:type="arc" weight="-1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaapNetIncomeLoss" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetIncomeLoss" xlink:to="loc_us-gaapProfitLoss" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLossAttributableToNoncontrollingInterest" xlink:label="loc_us-gaapNetIncomeLossAttributableToNoncontrollingInterest" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetIncomeLoss" xlink:to="loc_us-gaapNetIncomeLossAttributableToNoncontrollingInterest" xlink:type="arc" weight="-1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" xlink:label="loc_us-gaapOtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent" xlink:label="loc_us-gaapOtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapOtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" xlink:to="loc_us-gaapOtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaapComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest" xlink:to="loc_us-gaapProfitLoss" xlink:type="arc" weight="1" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest" xlink:to="loc_us-gaapOtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComprehensiveIncomeNetOfTax" xlink:label="loc_us-gaapComprehensiveIncomeNetOfTax" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapComprehensiveIncomeNetOfTax" xlink:to="loc_us-gaapComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest" xlink:label="loc_us-gaapComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapComprehensiveIncomeNetOfTax" xlink:to="loc_us-gaapComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest" xlink:type="arc" weight="-1" />
    </link:calculationLink>
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/StatementsOfStockholdersEquityDeficit" xlink:title="00000005 - Statement - Consolidated Statements of Stockholders&apos; Equity (Deficit) (Unaudited)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/StatementsOfStockholdersEquityDeficitParenthetical" xlink:title="00000006 - Statement - Consolidated Statements of Stockholders&apos; Equity (Deficit) (Unaudited) (Parenthetical)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/StatementsOfCashFlows" xlink:title="00000007 - Statement - Consolidated Statements of Cash Flows (Unaudited)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss" xlink:label="loc_us-gaapProfitLoss" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_us-gaapProfitLoss" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Depreciation" xlink:label="loc_us-gaapDepreciation" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_us-gaapDepreciation" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="fdct-20260331.xsd#FDCT_CommonStockIssuedForServices" xlink:label="loc_FDCTCommonStockIssuedForServices" />
      <link:calculationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_FDCTCommonStockIssuedForServices" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="fdct-20260331.xsd#FDCT_SeriesBPreferredIssuedForServices" xlink:label="loc_FDCTSeriesBPreferredIssuedForServices" />
      <link:calculationArc order="4" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_FDCTSeriesBPreferredIssuedForServices" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProvisionForDoubtfulAccounts" xlink:label="loc_us-gaapProvisionForDoubtfulAccounts" />
      <link:calculationArc order="5" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_us-gaapProvisionForDoubtfulAccounts" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnSaleOfPropertyPlantEquipment" xlink:label="loc_us-gaapGainLossOnSaleOfPropertyPlantEquipment" />
      <link:calculationArc order="6" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_us-gaapGainLossOnSaleOfPropertyPlantEquipment" xlink:type="arc" weight="-1" />
      <link:loc xlink:type="locator" xlink:href="fdct-20260331.xsd#FDCT_AcquiredIntangibleAssets" xlink:label="loc_FDCTAcquiredIntangibleAssets" />
      <link:calculationArc order="7" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_FDCTAcquiredIntangibleAssets" xlink:type="arc" weight="-1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable" xlink:label="loc_us-gaapIncreaseDecreaseInAccountsReceivable" />
      <link:calculationArc order="8" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_us-gaapIncreaseDecreaseInAccountsReceivable" xlink:type="arc" weight="-1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInPrepaidExpense" xlink:label="loc_us-gaapIncreaseDecreaseInPrepaidExpense" />
      <link:calculationArc order="9" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_us-gaapIncreaseDecreaseInPrepaidExpense" xlink:type="arc" weight="-1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInDueFromRelatedPartiesCurrent" xlink:label="loc_us-gaapIncreaseDecreaseInDueFromRelatedPartiesCurrent" />
      <link:calculationArc order="10" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_us-gaapIncreaseDecreaseInDueFromRelatedPartiesCurrent" xlink:type="arc" weight="-1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccountsPayable" xlink:label="loc_us-gaapIncreaseDecreaseInAccountsPayable" />
      <link:calculationArc order="11" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_us-gaapIncreaseDecreaseInAccountsPayable" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOtherCurrentLiabilities" xlink:label="loc_us-gaapIncreaseDecreaseInOtherCurrentLiabilities" />
      <link:calculationArc order="12" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_us-gaapIncreaseDecreaseInOtherCurrentLiabilities" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInInterestPayableNet" xlink:label="loc_us-gaapIncreaseDecreaseInInterestPayableNet" />
      <link:calculationArc order="13" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_us-gaapIncreaseDecreaseInInterestPayableNet" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="fdct-20260331.xsd#FDCT_IncreaseDecreaseInCustomerFunds" xlink:label="loc_FDCTIncreaseDecreaseInCustomerFunds" />
      <link:calculationArc order="14" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_FDCTIncreaseDecreaseInCustomerFunds" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInDerivativeLiabilities" xlink:label="loc_us-gaapIncreaseDecreaseInDerivativeLiabilities" />
      <link:calculationArc order="15" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_us-gaapIncreaseDecreaseInDerivativeLiabilities" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOperatingLeaseLiability" xlink:label="loc_us-gaapIncreaseDecreaseInOperatingLeaseLiability" />
      <link:calculationArc order="16" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_us-gaapIncreaseDecreaseInOperatingLeaseLiability" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInDeferredLiabilities" xlink:label="loc_us-gaapIncreaseDecreaseInDeferredLiabilities" />
      <link:calculationArc order="17" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_us-gaapIncreaseDecreaseInDeferredLiabilities" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInIncomeTaxesReceivable" xlink:label="loc_us-gaapIncreaseDecreaseInIncomeTaxesReceivable" />
      <link:calculationArc order="18" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_us-gaapIncreaseDecreaseInIncomeTaxesReceivable" xlink:type="arc" weight="-1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOtherReceivables" xlink:label="loc_us-gaapIncreaseDecreaseInOtherReceivables" />
      <link:calculationArc order="19" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_us-gaapIncreaseDecreaseInOtherReceivables" xlink:type="arc" weight="-1" />
      <link:loc xlink:type="locator" xlink:href="fdct-20260331.xsd#FDCT_IncreaseDecreaseInAccruedIncome" xlink:label="loc_FDCTIncreaseDecreaseInAccruedIncome" />
      <link:calculationArc order="20" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_FDCTIncreaseDecreaseInAccruedIncome" xlink:type="arc" weight="-1" />
      <link:loc xlink:type="locator" xlink:href="fdct-20260331.xsd#FDCT_IncreaseDecreaseInRightOfUseAssetLease" xlink:label="loc_FDCTIncreaseDecreaseInRightOfUseAssetLease" />
      <link:calculationArc order="21" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_FDCTIncreaseDecreaseInRightOfUseAssetLease" xlink:type="arc" weight="-1" />
      <link:loc xlink:type="locator" xlink:href="fdct-20260331.xsd#FDCT_IncreaseDecreaseInDueToAccruedExpensesRelatedParty" xlink:label="loc_FDCTIncreaseDecreaseInDueToAccruedExpensesRelatedParty" />
      <link:calculationArc order="22" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:to="loc_FDCTIncreaseDecreaseInDueToAccruedExpensesRelatedParty" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="loc_us-gaapNetCashProvidedByUsedInInvestingActivities" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToDevelopSoftware" xlink:label="loc_us-gaapPaymentsToDevelopSoftware" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInInvestingActivities" xlink:to="loc_us-gaapPaymentsToDevelopSoftware" xlink:type="arc" weight="-1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromSaleOfOtherInvestments" xlink:label="loc_us-gaapProceedsFromSaleOfOtherInvestments" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInInvestingActivities" xlink:to="loc_us-gaapProceedsFromSaleOfOtherInvestments" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="fdct-20260331.xsd#FDCT_PaymentsForProceedsFromChangesInPaidinCapital" xlink:label="loc_FDCTPaymentsForProceedsFromChangesInPaidinCapital" />
      <link:calculationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInInvestingActivities" xlink:to="loc_FDCTPaymentsForProceedsFromChangesInPaidinCapital" xlink:type="arc" weight="-1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="loc_us-gaapNetCashProvidedByUsedInFinancingActivities" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromRepaymentsOfLinesOfCredit" xlink:label="loc_us-gaapProceedsFromRepaymentsOfLinesOfCredit" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInFinancingActivities" xlink:to="loc_us-gaapProceedsFromRepaymentsOfLinesOfCredit" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromOtherShortTermDebt" xlink:label="loc_us-gaapProceedsFromOtherShortTermDebt" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInFinancingActivities" xlink:to="loc_us-gaapProceedsFromOtherShortTermDebt" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="fdct-20260331.xsd#FDCT_ProceedsFromSBALoan" xlink:label="loc_FDCTProceedsFromSBALoan" />
      <link:calculationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInFinancingActivities" xlink:to="loc_FDCTProceedsFromSBALoan" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromRepaymentsOfRelatedPartyDebt" xlink:label="loc_us-gaapProceedsFromRepaymentsOfRelatedPartyDebt" />
      <link:calculationArc order="4" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInFinancingActivities" xlink:to="loc_us-gaapProceedsFromRepaymentsOfRelatedPartyDebt" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromPaymentsToMinorityShareholders" xlink:label="loc_us-gaapProceedsFromPaymentsToMinorityShareholders" />
      <link:calculationArc order="5" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInFinancingActivities" xlink:to="loc_us-gaapProceedsFromPaymentsToMinorityShareholders" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="fdct-20260331.xsd#FDCT_ProceedsFromPaymentsToMinorityShareholdersInterest" xlink:label="loc_FDCTProceedsFromPaymentsToMinorityShareholdersInterest" />
      <link:calculationArc order="6" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapNetCashProvidedByUsedInFinancingActivities" xlink:to="loc_FDCTProceedsFromPaymentsToMinorityShareholdersInterest" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:label="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:to="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" xlink:type="arc" weight="1" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:to="loc_us-gaapNetCashProvidedByUsedInInvestingActivities" xlink:type="arc" weight="1" />
      <link:calculationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:to="loc_us-gaapNetCashProvidedByUsedInFinancingActivities" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" xlink:label="loc_us-gaapEffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" />
      <link:calculationArc order="4" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:to="loc_us-gaapEffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" xlink:type="arc" weight="1" />
    </link:calculationLink>
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/BusinessDescriptionAndNatureOfOperations" xlink:title="999008 - Disclosure - BUSINESS DESCRIPTION AND NATURE OF OPERATIONS" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/SummaryOfSignificantAccountingPolicies" xlink:title="999009 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/ManagementsPlans" xlink:title="999010 - Disclosure - MANAGEMENT&#8217;S PLANS" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/CapitalizedSoftwareCosts" xlink:title="999011 - Disclosure - CAPITALIZED SOFTWARE COSTS" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/RelatedPartyTransactions" xlink:title="999012 - Disclosure - RELATED PARTY TRANSACTIONS" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/LineOfCredit" xlink:title="999013 - Disclosure - LINE OF CREDIT" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/NotesPayable" xlink:title="999014 - Disclosure - NOTES PAYABLE" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/CommitmentsAndContingencies" xlink:title="999015 - Disclosure - COMMITMENTS AND CONTINGENCIES" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/StockholdersEquityDeficit" xlink:title="999016 - Disclosure - STOCKHOLDERS&#8217; EQUITY (DEFICIT)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/Warrants" xlink:title="999017 - Disclosure - WARRANTS" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/ComprehensiveIncome" xlink:title="999018 - Disclosure - COMPREHENSIVE INCOME" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/NoncontrollingInterest" xlink:title="999019 - Disclosure - NONCONTROLLING INTEREST" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/Off-balanceSheetArrangements" xlink:title="999020 - Disclosure - OFF-BALANCE SHEET ARRANGEMENTS" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/SubsequentEvents" xlink:title="999021 - Disclosure - SUBSEQUENT EVENTS" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/SummaryOfSignificantAccountingPoliciesPolicies" xlink:title="999022 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/BusinessDescriptionAndNatureOfOperationsTables" xlink:title="999023 - Disclosure - BUSINESS DESCRIPTION AND NATURE OF OPERATIONS (Tables)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/SummaryOfSignificantAccountingPoliciesTables" xlink:title="999024 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/StockholdersEquityDeficitTables" xlink:title="999025 - Disclosure - STOCKHOLDERS&#8217; EQUITY (DEFICIT) (Tables)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/ComprehensiveIncomeTables" xlink:title="999026 - Disclosure - COMPREHENSIVE INCOME (Tables)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/NoncontrollingInterestTables" xlink:title="999027 - Disclosure - NONCONTROLLING INTEREST (Tables)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/ScheduleOfConsolidatedSubsidiariesDetails" xlink:title="999028 - Disclosure - SCHEDULE OF CONSOLIDATED SUBSIDIARIES (Details)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/BusinessDescriptionAndNatureOfOperationsDetailsNarrative" xlink:title="999029 - Disclosure - BUSINESS DESCRIPTION AND NATURE OF OPERATIONS (Details Narrative)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/ScheduleOfRestatementOfPreviouslyIssuedFinancialStatementsDetails" xlink:title="999030 - Disclosure - SCHEDULE OF RESTATEMENT OF PREVIOUSLY ISSUED FINANCIAL STATEMENTS (Details)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/ScheduleOfCashCashEquivalentsAndRestrictedCashDetails" xlink:title="999031 - Disclosure - SCHEDULE OF CASH, CASH EQUIVALENTS, AND RESTRICTED CASH (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" xlink:label="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaapCashAndCashEquivalentsAtCarryingValue" />
      <link:calculationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" xlink:to="loc_us-gaapCashAndCashEquivalentsAtCarryingValue" xlink:type="arc" weight="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCashCurrent" xlink:label="loc_us-gaapRestrictedCashCurrent" />
      <link:calculationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" xlink:to="loc_us-gaapRestrictedCashCurrent" xlink:type="arc" weight="1" />
    </link:calculationLink>
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/ScheduleOfExchangeRateDetails" xlink:title="999032 - Disclosure - SCHEDULE OF EXCHANGE RATE (Details)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/SummaryOfSignificantAccountingPoliciesDetailsNarrative" xlink:title="999033 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details Narrative)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/ManagementsPlansDetailsNarrative" xlink:title="999034 - Disclosure - MANAGEMENT&#8217;S PLANS (Details Narrative)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/CapitalizedSoftwareCostsDetailsNarrative" xlink:title="999035 - Disclosure - CAPITALIZED SOFTWARE COSTS (Details Narrative)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/RelatedPartyTransactionsDetailsNarrative" xlink:title="999036 - Disclosure - RELATED PARTY TRANSACTIONS (Details Narrative)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/LineOfCreditDetailsNarrative" xlink:title="999037 - Disclosure - LINE OF CREDIT (Details Narrative)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/NotesPayableDetailsNarrative" xlink:title="999038 - Disclosure - NOTES PAYABLE (Details Narrative)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/CommitmentsAndContingenciesDetailsNarrative" xlink:title="999039 - Disclosure - COMMITMENTS AND CONTINGENCIES (Details Narrative)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/StockholdersEquityDeficitDetailsNarrative" xlink:title="999040 - Disclosure - STOCKHOLDERS&#8217; EQUITY (DEFICIT) (Details Narrative)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/ScheduleOfSeriesPreferredStockDetails" xlink:title="999041 - Disclosure - SCHEDULE OF SERIES A PREFERRED STOCK (Details)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/ScheduleOfSeriesPreferredStockDetailsParenthetical" xlink:title="999042 - Disclosure - SCHEDULE OF SERIES A PREFERRED STOCK (Details) (Parenthetical)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/ScheduleOfSeriesBPreferredStockDetails" xlink:title="999043 - Disclosure - SCHEDULE OF SERIES B PREFERRED STOCK (Details)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/ScheduleOfSeriesBPreferredStockDetailsParenthetical" xlink:title="999044 - Disclosure - SCHEDULE OF SERIES B PREFERRED STOCK (Details) (Parenthetical)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/WarrantsDetailsNarrative" xlink:title="999045 - Disclosure - WARRANTS (Details Narrative)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/ScheduleOfChangesInAccumulatedOtherComprehensiveIncomeDetails" xlink:title="999046 - Disclosure - SCHEDULE OF CHANGES IN ACCUMULATED OTHER COMPREHENSIVE INCOME (Details)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/ComprehensiveIncomeDetailsNarrative" xlink:title="999047 - Disclosure - COMPREHENSIVE INCOME (Details Narrative)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/ScheduleOfNoncontrollingInterestDetails" xlink:title="999048 - Disclosure - SCHEDULE OF NONCONTROLLING INTEREST (Details)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/NoncontrollingInterestDetailsNarrative" xlink:title="999049 - Disclosure - NONCONTROLLING INTEREST (Details Narrative)" />
    <link:calculationLink xlink:type="extended" xlink:role="http://fdctech.com/role/SubsequentEventsDetailsNarrative" xlink:title="999050 - Disclosure - SUBSEQUENT EVENTS (Details Narrative)" />
</link:linkbase>
