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

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:3f4355fa-486d-4c3b-935b-871a13373f3a,g:eb7c3e8e-82d4-4892-8c1c-9fcd547afe17-->
<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:roleRef roleURI="http://www.htgc.com/role/CONSOLIDATEDSTATEMENTSOFASSETSANDLIABILITIES" xlink:type="simple" xlink:href="htgc-20260331.xsd#CONSOLIDATEDSTATEMENTSOFASSETSANDLIABILITIES"/>
  <link:calculationLink xlink:role="http://www.htgc.com/role/CONSOLIDATEDSTATEMENTSOFASSETSANDLIABILITIES" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_a43a744a-ba1a-4397-abc6-6497084a6fad" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Assets"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestReceivable_89a80eb6-1284-4d9e-aab3-e2e99857ae0f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestReceivable"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_a43a744a-ba1a-4397-abc6-6497084a6fad" xlink:to="loc_us-gaap_InterestReceivable_89a80eb6-1284-4d9e-aab3-e2e99857ae0f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCash_6bb67edf-ee32-4bf8-ac12-ff354449fb10" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCash"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_a43a744a-ba1a-4397-abc6-6497084a6fad" xlink:to="loc_us-gaap_RestrictedCash_6bb67edf-ee32-4bf8-ac12-ff354449fb10" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_d04c4880-6abc-4d17-89c2-47dee4109f92" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_a43a744a-ba1a-4397-abc6-6497084a6fad" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_d04c4880-6abc-4d17-89c2-47dee4109f92" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_10f7c6bf-78dd-4758-976f-ec2305cf965a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_a43a744a-ba1a-4397-abc6-6497084a6fad" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_10f7c6bf-78dd-4758-976f-ec2305cf965a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseRightOfUseAsset_11f6655f-967c-4b0f-8c31-d4d4fdf8e070" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseRightOfUseAsset"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_a43a744a-ba1a-4397-abc6-6497084a6fad" xlink:to="loc_us-gaap_OperatingLeaseRightOfUseAsset_11f6655f-967c-4b0f-8c31-d4d4fdf8e070" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssets_b5227f49-eee8-45c0-acc4-cc981afcccbe" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherAssets"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_a43a744a-ba1a-4397-abc6-6497084a6fad" xlink:to="loc_us-gaap_OtherAssets_b5227f49-eee8-45c0-acc4-cc981afcccbe" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_70e8ea11-f736-4117-92ea-899728c9df1b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesAndStockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_0f4cd8ec-ad7f-4042-bf1f-433d47a07e0d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Liabilities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_70e8ea11-f736-4117-92ea-899728c9df1b" xlink:to="loc_us-gaap_Liabilities_0f4cd8ec-ad7f-4042-bf1f-433d47a07e0d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_c5f12000-b02a-4bd8-94ca-abafbc472b13" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_70e8ea11-f736-4117-92ea-899728c9df1b" xlink:to="loc_us-gaap_StockholdersEquity_c5f12000-b02a-4bd8-94ca-abafbc472b13" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_5d49d89b-373a-41ef-97f4-d082b6507e48" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Liabilities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_a1eafc72-0551-4c90-9cd5-058db68af10b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebt"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_5d49d89b-373a-41ef-97f4-d082b6507e48" xlink:to="loc_us-gaap_LongTermDebt_a1eafc72-0551-4c90-9cd5-058db68af10b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent_3df16a83-c85f-401e-b0ea-5bab09de9c57" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_5d49d89b-373a-41ef-97f4-d082b6507e48" xlink:to="loc_us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent_3df16a83-c85f-401e-b0ea-5bab09de9c57" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiability_39ef9c81-c1ad-4d0a-8f6b-9c7be16ce150" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiability"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_5d49d89b-373a-41ef-97f4-d082b6507e48" xlink:to="loc_us-gaap_OperatingLeaseLiability_39ef9c81-c1ad-4d0a-8f6b-9c7be16ce150" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_fc12095c-2f75-4fc1-995c-2757ad8a1378" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockValue_2ffb9c9c-d117-4aab-8559-746e183455a9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockValue"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_fc12095c-2f75-4fc1-995c-2757ad8a1378" xlink:to="loc_us-gaap_CommonStockValue_2ffb9c9c-d117-4aab-8559-746e183455a9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapital_349831ce-3f8b-420b-a1f1-bf2b7980773f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapital"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_fc12095c-2f75-4fc1-995c-2757ad8a1378" xlink:to="loc_us-gaap_AdditionalPaidInCapital_349831ce-3f8b-420b-a1f1-bf2b7980773f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_1f6f9005-f243-4e67-9c15-16a5aeec9287" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsAccumulatedDeficit"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_fc12095c-2f75-4fc1-995c-2757ad8a1378" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_1f6f9005-f243-4e67-9c15-16a5aeec9287" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.htgc.com/role/CONSOLIDATEDSTATEMENTSOFOPERATIONSunaudited" xlink:type="simple" xlink:href="htgc-20260331.xsd#CONSOLIDATEDSTATEMENTSOFOPERATIONSunaudited"/>
  <link:calculationLink xlink:role="http://www.htgc.com/role/CONSOLIDATEDSTATEMENTSOFOPERATIONSunaudited" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossInvestmentIncomeOperating_43fd9eb6-65ea-465e-8780-fb836d346507" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GrossInvestmentIncomeOperating"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FeeIncome_b44a0fb1-f2b1-423d-bc85-0e909b954e2e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FeeIncome"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_GrossInvestmentIncomeOperating_43fd9eb6-65ea-465e-8780-fb836d346507" xlink:to="loc_us-gaap_FeeIncome_b44a0fb1-f2b1-423d-bc85-0e909b954e2e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndDividendIncomeOperating_5513128b-da3d-485b-8f88-da39b5c24631" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestAndDividendIncomeOperating"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_GrossInvestmentIncomeOperating_43fd9eb6-65ea-465e-8780-fb836d346507" xlink:to="loc_us-gaap_InterestAndDividendIncomeOperating_5513128b-da3d-485b-8f88-da39b5c24631" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyRealizedAndUnrealizedGainLossOnInvestmentAndForeignCurrency_237f6fcc-9f3a-40e6-a351-957cf8e94f2b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentCompanyRealizedAndUnrealizedGainLossOnInvestmentAndForeignCurrency"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_RealizedInvestmentGainsLossAndGainLossOnExtinguishmentOfDebt_ef211655-2092-4619-a4fe-9c126499b236" xlink:href="htgc-20260331.xsd#htgc_RealizedInvestmentGainsLossAndGainLossOnExtinguishmentOfDebt"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InvestmentCompanyRealizedAndUnrealizedGainLossOnInvestmentAndForeignCurrency_237f6fcc-9f3a-40e6-a351-957cf8e94f2b" xlink:to="loc_htgc_RealizedInvestmentGainsLossAndGainLossOnExtinguishmentOfDebt_ef211655-2092-4619-a4fe-9c126499b236" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnInvestments_0f7bb724-984c-4683-9cbc-851edfd41691" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UnrealizedGainLossOnInvestments"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InvestmentCompanyRealizedAndUnrealizedGainLossOnInvestmentAndForeignCurrency_237f6fcc-9f3a-40e6-a351-957cf8e94f2b" xlink:to="loc_us-gaap_UnrealizedGainLossOnInvestments_0f7bb724-984c-4683-9cbc-851edfd41691" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_d479014d-9878-4dc2-aed3-ee9911a39728" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyRealizedAndUnrealizedGainLossOnInvestmentAndForeignCurrency_d8518e4c-19f7-4e4a-aa17-ecb850101a2e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentCompanyRealizedAndUnrealizedGainLossOnInvestmentAndForeignCurrency"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_d479014d-9878-4dc2-aed3-ee9911a39728" xlink:to="loc_us-gaap_InvestmentCompanyRealizedAndUnrealizedGainLossOnInvestmentAndForeignCurrency_d8518e4c-19f7-4e4a-aa17-ecb850101a2e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetInvestmentIncome_0654356a-eac8-4de0-ac3e-636ee4bcd551" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetInvestmentIncome"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_d479014d-9878-4dc2-aed3-ee9911a39728" xlink:to="loc_us-gaap_NetInvestmentIncome_0654356a-eac8-4de0-ac3e-636ee4bcd551" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_OperatingExpensesNet_1e585085-7c90-4319-a8cf-17329d1bb8a8" xlink:href="htgc-20260331.xsd#htgc_OperatingExpensesNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_ExpensesAllocatedToAdviserSubsidiary1_0a3c7e75-814a-4ed6-83c6-2d489b121269" xlink:href="htgc-20260331.xsd#htgc_ExpensesAllocatedToAdviserSubsidiary1"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_htgc_OperatingExpensesNet_1e585085-7c90-4319-a8cf-17329d1bb8a8" xlink:to="loc_htgc_ExpensesAllocatedToAdviserSubsidiary1_0a3c7e75-814a-4ed6-83c6-2d489b121269" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingExpenses_c0887a57-3d56-4fdc-bfa0-5e242bb5eb86" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingExpenses"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_htgc_OperatingExpensesNet_1e585085-7c90-4319-a8cf-17329d1bb8a8" xlink:to="loc_us-gaap_OperatingExpenses_c0887a57-3d56-4fdc-bfa0-5e242bb5eb86" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndDividendIncomeOperating_c73c05f9-a343-4ee3-867f-99f6ab345dd0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestAndDividendIncomeOperating"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeOperatingPaidInKind_fccc6431-cfb5-40d0-b107-f88414d4d781" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestIncomeOperatingPaidInKind"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestAndDividendIncomeOperating_c73c05f9-a343-4ee3-867f-99f6ab345dd0" xlink:to="loc_us-gaap_InterestIncomeOperatingPaidInKind_fccc6431-cfb5-40d0-b107-f88414d4d781" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndDividendIncomeOperatingPaidInCash_abe72c42-7972-4c92-a0dd-0c6ca78ddd64" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestAndDividendIncomeOperatingPaidInCash"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestAndDividendIncomeOperating_c73c05f9-a343-4ee3-867f-99f6ab345dd0" xlink:to="loc_us-gaap_InterestAndDividendIncomeOperatingPaidInCash_abe72c42-7972-4c92-a0dd-0c6ca78ddd64" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingExpenses_a143ae73-87ee-4ac1-bab9-ffc1f504601d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingExpenses"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_EmployeeCompensation_8b4355df-c630-4122-b2d4-2b672069fc2f" xlink:href="htgc-20260331.xsd#htgc_EmployeeCompensation"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_a143ae73-87ee-4ac1-bab9-ffc1f504601d" xlink:to="loc_htgc_EmployeeCompensation_8b4355df-c630-4122-b2d4-2b672069fc2f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDebt_92ca149b-62e0-4541-a409-77c93672405d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpenseDebt"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_a143ae73-87ee-4ac1-bab9-ffc1f504601d" xlink:to="loc_us-gaap_InterestExpenseDebt_92ca149b-62e0-4541-a409-77c93672405d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtRelatedCommitmentFeesAndDebtIssuanceCosts_0063bc08-241b-4741-b497-70712c835cdb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtRelatedCommitmentFeesAndDebtIssuanceCosts"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_a143ae73-87ee-4ac1-bab9-ffc1f504601d" xlink:to="loc_us-gaap_DebtRelatedCommitmentFeesAndDebtIssuanceCosts_0063bc08-241b-4741-b497-70712c835cdb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_d591f453-420d-4a26-9a8b-fd74122fcfdd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpense"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_a143ae73-87ee-4ac1-bab9-ffc1f504601d" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_d591f453-420d-4a26-9a8b-fd74122fcfdd" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeOperatingTaxExpenseBenefit_8292f06e-a250-4c9e-b41a-531fd0f0b2af" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentIncomeOperatingTaxExpenseBenefit"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_a143ae73-87ee-4ac1-bab9-ffc1f504601d" xlink:to="loc_us-gaap_InvestmentIncomeOperatingTaxExpenseBenefit_8292f06e-a250-4c9e-b41a-531fd0f0b2af" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_EmployeeCompensation_b3996fc7-5b0b-4ace-b1da-81dd112d8bac" xlink:href="htgc-20260331.xsd#htgc_EmployeeCompensation"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LaborAndRelatedExpense_50b28ac6-afab-465e-85ed-b72c994946d7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LaborAndRelatedExpense"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_htgc_EmployeeCompensation_b3996fc7-5b0b-4ace-b1da-81dd112d8bac" xlink:to="loc_us-gaap_LaborAndRelatedExpense_50b28ac6-afab-465e-85ed-b72c994946d7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeBenefitsAndShareBasedCompensation_cce881a1-0e2e-4fdb-8de9-31c57dad9e81" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeBenefitsAndShareBasedCompensation"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_htgc_EmployeeCompensation_b3996fc7-5b0b-4ace-b1da-81dd112d8bac" xlink:to="loc_us-gaap_EmployeeBenefitsAndShareBasedCompensation_cce881a1-0e2e-4fdb-8de9-31c57dad9e81" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetInvestmentIncome_4985092d-6df2-4eab-9981-31e4130b0492" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetInvestmentIncome"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossInvestmentIncomeOperating_026d551d-84eb-48ab-bca5-fadac54fe0a3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GrossInvestmentIncomeOperating"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetInvestmentIncome_4985092d-6df2-4eab-9981-31e4130b0492" xlink:to="loc_us-gaap_GrossInvestmentIncomeOperating_026d551d-84eb-48ab-bca5-fadac54fe0a3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_OperatingExpensesNet_fe856294-5dbf-47b6-b653-d49388043d0b" xlink:href="htgc-20260331.xsd#htgc_OperatingExpensesNet"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetInvestmentIncome_4985092d-6df2-4eab-9981-31e4130b0492" xlink:to="loc_htgc_OperatingExpensesNet_fe856294-5dbf-47b6-b653-d49388043d0b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_RealizedInvestmentGainsLossAndGainLossOnExtinguishmentOfDebt_4d8faed0-c4bf-4b5f-bf6e-1a84191a34c4" xlink:href="htgc-20260331.xsd#htgc_RealizedInvestmentGainsLossAndGainLossOnExtinguishmentOfDebt"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_6eb118e2-9ad5-47ef-8db1-ba60b000661b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_htgc_RealizedInvestmentGainsLossAndGainLossOnExtinguishmentOfDebt_4d8faed0-c4bf-4b5f-bf6e-1a84191a34c4" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_6eb118e2-9ad5-47ef-8db1-ba60b000661b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealizedInvestmentGainsLosses_5192f1fe-8c46-416e-9250-e9fecb77fae6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RealizedInvestmentGainsLosses"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_htgc_RealizedInvestmentGainsLossAndGainLossOnExtinguishmentOfDebt_4d8faed0-c4bf-4b5f-bf6e-1a84191a34c4" xlink:to="loc_us-gaap_RealizedInvestmentGainsLosses_5192f1fe-8c46-416e-9250-e9fecb77fae6" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.htgc.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWSunaudited" xlink:type="simple" xlink:href="htgc-20260331.xsd#CONSOLIDATEDSTATEMENTSOFCASHFLOWSunaudited"/>
  <link:calculationLink xlink:role="http://www.htgc.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWSunaudited" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_21c1006a-84a9-4345-9a9f-be1da60390df" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_413bb9cb-8251-4d8f-9428-94e338a43707" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_21c1006a-84a9-4345-9a9f-be1da60390df" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_413bb9cb-8251-4d8f-9428-94e338a43707" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_cbededbd-a65e-4ebf-8fc4-a512c13545ba" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_21c1006a-84a9-4345-9a9f-be1da60390df" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_cbededbd-a65e-4ebf-8fc4-a512c13545ba" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_96ff9b61-8a8e-4912-b527-46612c0392de" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_21c1006a-84a9-4345-9a9f-be1da60390df" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_96ff9b61-8a8e-4912-b527-46612c0392de" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_94eb4613-d12f-4a72-b3e6-cd475d31e9cc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_e1617cfc-2c57-47ce-bc61-79356129f256" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_94eb4613-d12f-4a72-b3e6-cd475d31e9cc" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_e1617cfc-2c57-47ce-bc61-79356129f256" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfStockIssuanceCosts_d0116ba4-f5f4-430b-92e3-61800e8c9597" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsOfStockIssuanceCosts"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_94eb4613-d12f-4a72-b3e6-cd475d31e9cc" xlink:to="loc_us-gaap_PaymentsOfStockIssuanceCosts_d0116ba4-f5f4-430b-92e3-61800e8c9597" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_fe5f62e4-7617-4e25-8dcf-06e62fc2712f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_94eb4613-d12f-4a72-b3e6-cd475d31e9cc" xlink:to="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_fe5f62e4-7617-4e25-8dcf-06e62fc2712f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfDividends_d710c0ff-1d86-460f-8881-517452c74b6c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsOfDividends"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_94eb4613-d12f-4a72-b3e6-cd475d31e9cc" xlink:to="loc_us-gaap_PaymentsOfDividends_d710c0ff-1d86-460f-8881-517452c74b6c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfDebt_2db3f48a-7d9a-4015-8065-ed9bc365048b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromIssuanceOfDebt"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_94eb4613-d12f-4a72-b3e6-cd475d31e9cc" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfDebt_2db3f48a-7d9a-4015-8065-ed9bc365048b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepaymentsOfDebt_3bbceed0-f253-4088-b2e9-46d2b8f19a63" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RepaymentsOfDebt"/>
    <link:calculationArc order="6" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_94eb4613-d12f-4a72-b3e6-cd475d31e9cc" xlink:to="loc_us-gaap_RepaymentsOfDebt_3bbceed0-f253-4088-b2e9-46d2b8f19a63" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfDebtIssuanceCosts_10370743-3930-4e5f-b899-321f97e2efed" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsOfDebtIssuanceCosts"/>
    <link:calculationArc order="7" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_94eb4613-d12f-4a72-b3e6-cd475d31e9cc" xlink:to="loc_us-gaap_PaymentsOfDebtIssuanceCosts_10370743-3930-4e5f-b899-321f97e2efed" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_PaymentOfFeesForCreditFacilities_d6797222-233e-4c0b-b062-7ff9d2ec6a53" xlink:href="htgc-20260331.xsd#htgc_PaymentOfFeesForCreditFacilities"/>
    <link:calculationArc order="8" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_94eb4613-d12f-4a72-b3e6-cd475d31e9cc" xlink:to="loc_htgc_PaymentOfFeesForCreditFacilities_d6797222-233e-4c0b-b062-7ff9d2ec6a53" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_9dc2eeed-e8d6-408c-b62c-bb131b75c39e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireProductiveAssets_97d226c7-7256-4223-b279-5abcfeccc431" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquireProductiveAssets"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_9dc2eeed-e8d6-408c-b62c-bb131b75c39e" xlink:to="loc_us-gaap_PaymentsToAcquireProductiveAssets_97d226c7-7256-4223-b279-5abcfeccc431" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_9b126bc8-87b3-4180-80f1-4c29db79b0a3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_us-gaap_NetIncomeLoss_9b126bc8-87b3-4180-80f1-4c29db79b0a3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForPurchaseOfInvestmentOperatingActivity_c85a49fe-e38a-4f27-a0a4-686001397ca8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsForPurchaseOfInvestmentOperatingActivity"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_us-gaap_PaymentsForPurchaseOfInvestmentOperatingActivity_c85a49fe-e38a-4f27-a0a4-686001397ca8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_FundingAssignedToAdviserFunds_866c5031-5fbe-47a7-9a32-73f8e60367e1" xlink:href="htgc-20260331.xsd#htgc_FundingAssignedToAdviserFunds"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_htgc_FundingAssignedToAdviserFunds_866c5031-5fbe-47a7-9a32-73f8e60367e1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromDispositionOfInvestmentOperatingActivity_be4e22bf-bbaa-4cec-8d81-6c13984a0c37" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromDispositionOfInvestmentOperatingActivity"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_us-gaap_ProceedsFromDispositionOfInvestmentOperatingActivity_be4e22bf-bbaa-4cec-8d81-6c13984a0c37" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_ProceedsFromTheSaleOfDebtInvestments_977379ee-3eb2-4481-b58a-17034c9a5365" xlink:href="htgc-20260331.xsd#htgc_ProceedsFromTheSaleOfDebtInvestments"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_htgc_ProceedsFromTheSaleOfDebtInvestments_977379ee-3eb2-4481-b58a-17034c9a5365" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_ProceedsFromDispositionOfInvestmentEquityAndWarrantsInvestmentsOperatingActivity_8ab8e7ea-891c-4783-99e8-c10cce5794c1" xlink:href="htgc-20260331.xsd#htgc_ProceedsFromDispositionOfInvestmentEquityAndWarrantsInvestmentsOperatingActivity"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_htgc_ProceedsFromDispositionOfInvestmentEquityAndWarrantsInvestmentsOperatingActivity_8ab8e7ea-891c-4783-99e8-c10cce5794c1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax_302ae2e0-b353-41b3-8bd1-d37d75e42b1a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax"/>
    <link:calculationArc order="7" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_us-gaap_UnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax_302ae2e0-b353-41b3-8bd1-d37d75e42b1a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealizedGainLossInvestmentAndDerivativeOperatingAfterTax_ba31a05d-3138-477e-a1b9-7c333ca02bfa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RealizedGainLossInvestmentAndDerivativeOperatingAfterTax"/>
    <link:calculationArc order="8" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_us-gaap_RealizedGainLossInvestmentAndDerivativeOperatingAfterTax_ba31a05d-3138-477e-a1b9-7c333ca02bfa" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeOperatingPaidInKind_47e2d387-da25-439b-8a93-68e4f9703ec5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestIncomeOperatingPaidInKind"/>
    <link:calculationArc order="9" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_us-gaap_InterestIncomeOperatingPaidInKind_47e2d387-da25-439b-8a93-68e4f9703ec5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_eb61efb7-47cc-44d7-bec3-ff731795d297" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments"/>
    <link:calculationArc order="10" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_eb61efb7-47cc-44d7-bec3-ff731795d297" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_AccretionAmortizationOfDiscountsAndPremiumsInvestmentsConvertibleNotes_0039404c-6ecd-4b81-a348-07a82e71e976" xlink:href="htgc-20260331.xsd#htgc_AccretionAmortizationOfDiscountsAndPremiumsInvestmentsConvertibleNotes"/>
    <link:calculationArc order="11" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_htgc_AccretionAmortizationOfDiscountsAndPremiumsInvestmentsConvertibleNotes_0039404c-6ecd-4b81-a348-07a82e71e976" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_70926d54-3b1c-4061-92a5-fcc2dcae065e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:calculationArc order="12" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_70926d54-3b1c-4061-92a5-fcc2dcae065e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_AccretionOfLoanExitFees_93bbc8a1-15f5-49f6-b77b-4be4d7ffb67d" xlink:href="htgc-20260331.xsd#htgc_AccretionOfLoanExitFees"/>
    <link:calculationArc order="13" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_htgc_AccretionOfLoanExitFees_93bbc8a1-15f5-49f6-b77b-4be4d7ffb67d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_ChangeInLoanIncomeNetOfCollections_bbc57a64-d652-4ae3-a0ba-b6e4b15eb147" xlink:href="htgc-20260331.xsd#htgc_ChangeInLoanIncomeNetOfCollections"/>
    <link:calculationArc order="14" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_htgc_ChangeInLoanIncomeNetOfCollections_bbc57a64-d652-4ae3-a0ba-b6e4b15eb147" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_UnearnedFeesRelatedToUnfundedCommitments_05d09934-1f1c-4ca9-b1f9-3101acf56975" xlink:href="htgc-20260331.xsd#htgc_UnearnedFeesRelatedToUnfundedCommitments"/>
    <link:calculationArc order="15" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_htgc_UnearnedFeesRelatedToUnfundedCommitments_05d09934-1f1c-4ca9-b1f9-3101acf56975" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_644e2510-c519-4901-be43-b965f0956370" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfFinancingCostsAndDiscounts"/>
    <link:calculationArc order="16" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_644e2510-c519-4901-be43-b965f0956370" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationAndAmortization_74ec9b24-d502-4ede-a63b-7c73be6bc727" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationAndAmortization"/>
    <link:calculationArc order="17" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_us-gaap_DepreciationAndAmortization_74ec9b24-d502-4ede-a63b-7c73be6bc727" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_0cd4dd4a-0c96-4898-acc0-9f38374c6a76" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensation"/>
    <link:calculationArc order="18" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_us-gaap_ShareBasedCompensation_0cd4dd4a-0c96-4898-acc0-9f38374c6a76" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccruedInterestReceivableNet_019d4087-bcb8-7525-841f-8e11e1ef0651" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInAccruedInterestReceivableNet"/>
    <link:calculationArc order="19" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_us-gaap_IncreaseDecreaseInAccruedInterestReceivableNet_019d4087-bcb8-7525-841f-8e11e1ef0651" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingAssets_019d40a4-8568-7d2b-af3b-a3ef52af0706" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInOtherOperatingAssets"/>
    <link:calculationArc order="20" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherOperatingAssets_019d40a4-8568-7d2b-af3b-a3ef52af0706" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccruedLiabilities_019d7707-e25b-7865-b688-708ed41740aa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInAccruedLiabilities"/>
    <link:calculationArc order="21" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_9281a7f0-af8b-4e8a-8378-86f20ba897b4" xlink:to="loc_us-gaap_IncreaseDecreaseInAccruedLiabilities_019d7707-e25b-7865-b688-708ed41740aa" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.htgc.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWSunauditedParenthetical" xlink:type="simple" xlink:href="htgc-20260331.xsd#CONSOLIDATEDSTATEMENTSOFCASHFLOWSunauditedParenthetical"/>
  <link:calculationLink xlink:role="http://www.htgc.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWSunauditedParenthetical" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_273da15c-84af-49e2-9911-b922cead86bd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCash_04c15425-dc0a-46cf-a003-2ba7a46412ae" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCash"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_273da15c-84af-49e2-9911-b922cead86bd" xlink:to="loc_us-gaap_RestrictedCash_04c15425-dc0a-46cf-a003-2ba7a46412ae" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_8d62cb98-3832-401a-bb7c-1215ce342a7c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_273da15c-84af-49e2-9911-b922cead86bd" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_8d62cb98-3832-401a-bb7c-1215ce342a7c" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.htgc.com/role/InvestmentsScheduleofDerivativeInstrumentsDetails" xlink:type="simple" xlink:href="htgc-20260331.xsd#InvestmentsScheduleofDerivativeInstrumentsDetails"/>
  <link:calculationLink xlink:role="http://www.htgc.com/role/InvestmentsScheduleofDerivativeInstrumentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealizedAndUnrealizedGainLossInvestmentAndDerivativeOperatingAfterTax_019ce6b5-f576-7289-8bde-d998dfcdcc59" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RealizedAndUnrealizedGainLossInvestmentAndDerivativeOperatingAfterTax"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnDerivatives_019ce6b5-f576-7a32-906c-0ed056046c16" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UnrealizedGainLossOnDerivatives"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_RealizedAndUnrealizedGainLossInvestmentAndDerivativeOperatingAfterTax_019ce6b5-f576-7289-8bde-d998dfcdcc59" xlink:to="loc_us-gaap_UnrealizedGainLossOnDerivatives_019ce6b5-f576-7a32-906c-0ed056046c16" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.htgc.com/role/EarningsPerShareScheduleofBasicandDilutedEarningsPerShareDetails" xlink:type="simple" xlink:href="htgc-20260331.xsd#EarningsPerShareScheduleofBasicandDilutedEarningsPerShareDetails"/>
  <link:calculationLink xlink:role="http://www.htgc.com/role/EarningsPerShareScheduleofBasicandDilutedEarningsPerShareDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_117075e3-9a0f-4438-bf50-a077f50ff7a7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyDividendDistribution_7bd1327a-6e19-4334-9e2d-fb5c71679f73" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentCompanyDividendDistribution"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_117075e3-9a0f-4438-bf50-a077f50ff7a7" xlink:to="loc_us-gaap_InvestmentCompanyDividendDistribution_7bd1327a-6e19-4334-9e2d-fb5c71679f73" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UndistributedEarnings_54b494a9-792e-44c6-b5f4-96340aeec4bc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UndistributedEarnings"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_117075e3-9a0f-4438-bf50-a077f50ff7a7" xlink:to="loc_us-gaap_UndistributedEarnings_54b494a9-792e-44c6-b5f4-96340aeec4bc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_0cca4f6d-3fe1-4197-9bf8-194eadb3576b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_be2f620d-754a-4719-8baa-8706fc79d011" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_0cca4f6d-3fe1-4197-9bf8-194eadb3576b" xlink:to="loc_us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_be2f620d-754a-4719-8baa-8706fc79d011" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_68019b0a-b0c1-480d-8f82-b92683f344d4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_0cca4f6d-3fe1-4197-9bf8-194eadb3576b" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_68019b0a-b0c1-480d-8f82-b92683f344d4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_753033de-d9ec-4cc5-81f4-5f454cb8d57d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_0cca4f6d-3fe1-4197-9bf8-194eadb3576b" xlink:to="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_753033de-d9ec-4cc5-81f4-5f454cb8d57d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UndistributedEarningsLossAvailableToCommonShareholdersBasic_948dab43-b171-44f0-a279-c8c3c7a97351" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UndistributedEarningsLossAvailableToCommonShareholdersBasic"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_be76150e-9484-4d66-9fa9-cac33e386cac" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_UndistributedEarningsLossAvailableToCommonShareholdersBasic_948dab43-b171-44f0-a279-c8c3c7a97351" xlink:to="loc_us-gaap_NetIncomeLoss_be76150e-9484-4d66-9fa9-cac33e386cac" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyDividendDistribution_de53fa2a-de35-4dc9-847f-e0db2ef9faa3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentCompanyDividendDistribution"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_UndistributedEarningsLossAvailableToCommonShareholdersBasic_948dab43-b171-44f0-a279-c8c3c7a97351" xlink:to="loc_us-gaap_InvestmentCompanyDividendDistribution_de53fa2a-de35-4dc9-847f-e0db2ef9faa3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_fd225dfb-acf9-4b07-8d82-72d0137abfb8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_4b538144-5339-4325-9d15-752b2c1b6ecf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_fd225dfb-acf9-4b07-8d82-72d0137abfb8" xlink:to="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_4b538144-5339-4325-9d15-752b2c1b6ecf" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DilutiveSecuritiesEffectOnBasicEarningsPerShareOther_0ca3331a-2723-4ab4-adac-1785df0cf021" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DilutiveSecuritiesEffectOnBasicEarningsPerShareOther"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_fd225dfb-acf9-4b07-8d82-72d0137abfb8" xlink:to="loc_us-gaap_DilutiveSecuritiesEffectOnBasicEarningsPerShareOther_0ca3331a-2723-4ab4-adac-1785df0cf021" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.htgc.com/role/FinancialHighlightsDetails" xlink:type="simple" xlink:href="htgc-20260331.xsd#FinancialHighlightsDetails"/>
  <link:calculationLink xlink:role="http://www.htgc.com/role/FinancialHighlightsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyInvestmentIncomeLossFromOperationsPerShare_d136940e-abda-480e-9484-541da1b3cf8b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentCompanyInvestmentIncomeLossFromOperationsPerShare"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyRealizedGainLossOnInvestmentPerShare_4a0427b4-3403-49d4-a994-a207dee37543" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentCompanyRealizedGainLossOnInvestmentPerShare"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InvestmentCompanyInvestmentIncomeLossFromOperationsPerShare_d136940e-abda-480e-9484-541da1b3cf8b" xlink:to="loc_us-gaap_InvestmentCompanyRealizedGainLossOnInvestmentPerShare_4a0427b4-3403-49d4-a994-a207dee37543" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyUnrealizedGainLossOnInvestmentPerShare_3c9af633-25c2-4335-bbfa-b1b9ba962154" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentCompanyUnrealizedGainLossOnInvestmentPerShare"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InvestmentCompanyInvestmentIncomeLossFromOperationsPerShare_d136940e-abda-480e-9484-541da1b3cf8b" xlink:to="loc_us-gaap_InvestmentCompanyUnrealizedGainLossOnInvestmentPerShare_3c9af633-25c2-4335-bbfa-b1b9ba962154" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_InvestmentCompanyGainLossOnNetInvestmentPerShare_b4aee372-fb71-4256-86e0-996d5fdec600" xlink:href="htgc-20260331.xsd#htgc_InvestmentCompanyGainLossOnNetInvestmentPerShare"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InvestmentCompanyInvestmentIncomeLossFromOperationsPerShare_d136940e-abda-480e-9484-541da1b3cf8b" xlink:to="loc_htgc_InvestmentCompanyGainLossOnNetInvestmentPerShare_b4aee372-fb71-4256-86e0-996d5fdec600" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.htgc.com/role/CommitmentsandContingenciesScheduleofUnencumberedUnfundedCommitmentsDetails" xlink:type="simple" xlink:href="htgc-20260331.xsd#CommitmentsandContingenciesScheduleofUnencumberedUnfundedCommitmentsDetails"/>
  <link:calculationLink xlink:role="http://www.htgc.com/role/CommitmentsandContingenciesScheduleofUnencumberedUnfundedCommitmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019d4380-09dc-7bf1-b944-b9e9c1d9216d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_UnfundedCommitmentsDueInFourthYear_019d4380-09dc-7a35-9c01-8f75a83191cb" xlink:href="htgc-20260331.xsd#htgc_UnfundedCommitmentsDueInFourthYear"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019d4380-09dc-7bf1-b944-b9e9c1d9216d" xlink:to="loc_htgc_UnfundedCommitmentsDueInFourthYear_019d4380-09dc-7a35-9c01-8f75a83191cb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_UnfundedCommitmentsDueInSixthYear_019d4380-09dc-729d-8022-b3cc987abb26" xlink:href="htgc-20260331.xsd#htgc_UnfundedCommitmentsDueInSixthYear"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019d4380-09dc-7bf1-b944-b9e9c1d9216d" xlink:to="loc_htgc_UnfundedCommitmentsDueInSixthYear_019d4380-09dc-729d-8022-b3cc987abb26" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.htgc.com/role/CommitmentsandContingenciesScheduleofUnencumberedUnfundedCommitmentsDetails_1" xlink:type="simple" xlink:href="htgc-20260331.xsd#CommitmentsandContingenciesScheduleofUnencumberedUnfundedCommitmentsDetails_1"/>
  <link:calculationLink xlink:role="http://www.htgc.com/role/CommitmentsandContingenciesScheduleofUnencumberedUnfundedCommitmentsDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019cf442-4fdd-7d6e-908a-9c407479320c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_UnfundedCommitmentsDueInRemainderOfFiscalYear_019cf442-4fdd-7861-a032-0c16e1f309dc" xlink:href="htgc-20260331.xsd#htgc_UnfundedCommitmentsDueInRemainderOfFiscalYear"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019cf442-4fdd-7d6e-908a-9c407479320c" xlink:to="loc_htgc_UnfundedCommitmentsDueInRemainderOfFiscalYear_019cf442-4fdd-7861-a032-0c16e1f309dc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_UnfundedCommitmentsDueInOneYear_019cf442-4fdd-76af-90f9-66b051bda9c4" xlink:href="htgc-20260331.xsd#htgc_UnfundedCommitmentsDueInOneYear"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019cf442-4fdd-7d6e-908a-9c407479320c" xlink:to="loc_htgc_UnfundedCommitmentsDueInOneYear_019cf442-4fdd-76af-90f9-66b051bda9c4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_UnfundedCommitmentsDueInSecondYear_019d437f-1256-78a9-940e-6d4dccd16a83" xlink:href="htgc-20260331.xsd#htgc_UnfundedCommitmentsDueInSecondYear"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019cf442-4fdd-7d6e-908a-9c407479320c" xlink:to="loc_htgc_UnfundedCommitmentsDueInSecondYear_019d437f-1256-78a9-940e-6d4dccd16a83" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_UnfundedCommitmentsDueInThirdYear_019d437f-1256-7f14-8d0a-0f7575174615" xlink:href="htgc-20260331.xsd#htgc_UnfundedCommitmentsDueInThirdYear"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019cf442-4fdd-7d6e-908a-9c407479320c" xlink:to="loc_htgc_UnfundedCommitmentsDueInThirdYear_019d437f-1256-7f14-8d0a-0f7575174615" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_UnfundedCommitmentsDueInFourthYear_019d437f-1256-7a6a-af21-6d5d36e49475" xlink:href="htgc-20260331.xsd#htgc_UnfundedCommitmentsDueInFourthYear"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019cf442-4fdd-7d6e-908a-9c407479320c" xlink:to="loc_htgc_UnfundedCommitmentsDueInFourthYear_019d437f-1256-7a6a-af21-6d5d36e49475" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_UnfundedCommitmentsDueInFifthYear_019d437f-1256-7842-aabd-6ffcb6cdef4d" xlink:href="htgc-20260331.xsd#htgc_UnfundedCommitmentsDueInFifthYear"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019cf442-4fdd-7d6e-908a-9c407479320c" xlink:to="loc_htgc_UnfundedCommitmentsDueInFifthYear_019d437f-1256-7842-aabd-6ffcb6cdef4d" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.htgc.com/role/CommitmentsandContingenciesScheduleofContractualObligationsDetails" xlink:type="simple" xlink:href="htgc-20260331.xsd#CommitmentsandContingenciesScheduleofContractualObligationsDetails"/>
  <link:calculationLink xlink:role="http://www.htgc.com/role/CommitmentsandContingenciesScheduleofContractualObligationsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_aaac11f8-2c56-47aa-87d9-330b81ac5b8a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebt"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive_25058ccf-8847-44e1-b4c7-a0f4bf8a6702" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebt_aaac11f8-2c56-47aa-87d9-330b81ac5b8a" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive_25058ccf-8847-44e1-b4c7-a0f4bf8a6702" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_7a810a1c-bd95-4bbb-b916-63a44bee9682" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebt_aaac11f8-2c56-47aa-87d9-330b81ac5b8a" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_7a810a1c-bd95-4bbb-b916-63a44bee9682" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturingInYearsFourAndFive_4ec64915-1b4b-42c7-ac32-268ef1027d79" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtMaturingInYearsFourAndFive"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebt_aaac11f8-2c56-47aa-87d9-330b81ac5b8a" xlink:to="loc_us-gaap_LongTermDebtMaturingInYearsFourAndFive_4ec64915-1b4b-42c7-ac32-268ef1027d79" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturingInYearsTwoAndThree_476ff070-b458-4b3f-bce2-16f8de0c058f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtMaturingInYearsTwoAndThree"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebt_aaac11f8-2c56-47aa-87d9-330b81ac5b8a" xlink:to="loc_us-gaap_LongTermDebtMaturingInYearsTwoAndThree_476ff070-b458-4b3f-bce2-16f8de0c058f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractualObligation_851cae2c-9b30-4fd6-9cb6-c2f66c9aa6c9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractualObligation"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractualObligationDueInNextTwelveMonths_30b56698-7842-4ac3-9ee4-3ea6d5db4f0c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractualObligationDueInNextTwelveMonths"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ContractualObligation_851cae2c-9b30-4fd6-9cb6-c2f66c9aa6c9" xlink:to="loc_us-gaap_ContractualObligationDueInNextTwelveMonths_30b56698-7842-4ac3-9ee4-3ea6d5db4f0c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractualObligationDueInSecondAndThirdYear_69bcb5a5-b2b3-4cea-a6be-d4142e0bea7b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractualObligationDueInSecondAndThirdYear"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ContractualObligation_851cae2c-9b30-4fd6-9cb6-c2f66c9aa6c9" xlink:to="loc_us-gaap_ContractualObligationDueInSecondAndThirdYear_69bcb5a5-b2b3-4cea-a6be-d4142e0bea7b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractualObligationDueInFourthAndFifthYear_e127446d-17e0-45ce-ad48-8714b464b62f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractualObligationDueInFourthAndFifthYear"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ContractualObligation_851cae2c-9b30-4fd6-9cb6-c2f66c9aa6c9" xlink:to="loc_us-gaap_ContractualObligationDueInFourthAndFifthYear_e127446d-17e0-45ce-ad48-8714b464b62f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractualObligationDueAfterFifthYear_fe7fc331-fc51-4b7d-9924-857e53b9e336" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractualObligationDueAfterFifthYear"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ContractualObligation_851cae2c-9b30-4fd6-9cb6-c2f66c9aa6c9" xlink:to="loc_us-gaap_ContractualObligationDueAfterFifthYear_fe7fc331-fc51-4b7d-9924-857e53b9e336" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_0e021671-466b-48e4-a417-5aaf8474ba55" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_LesseeOperatingLeaseLiabilityToBePaidYearTwoAndThree_880a701e-007f-4b4b-b47e-018485ca5c9e" xlink:href="htgc-20260331.xsd#htgc_LesseeOperatingLeaseLiabilityToBePaidYearTwoAndThree"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_0e021671-466b-48e4-a417-5aaf8474ba55" xlink:to="loc_htgc_LesseeOperatingLeaseLiabilityToBePaidYearTwoAndThree_880a701e-007f-4b4b-b47e-018485ca5c9e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive_28b8b0cf-ac1b-4e0b-a3a8-761d873edded" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_0e021671-466b-48e4-a417-5aaf8474ba55" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive_28b8b0cf-ac1b-4e0b-a3a8-761d873edded" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_3568571a-9505-40eb-a1df-e0b900480a63" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_0e021671-466b-48e4-a417-5aaf8474ba55" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_3568571a-9505-40eb-a1df-e0b900480a63" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_LesseeOperatingLeaseLiabilityToBePaidYearFourAndFive_a5aac5b2-9314-4bab-95c2-84c394619b76" xlink:href="htgc-20260331.xsd#htgc_LesseeOperatingLeaseLiabilityToBePaidYearFourAndFive"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_0e021671-466b-48e4-a417-5aaf8474ba55" xlink:to="loc_htgc_LesseeOperatingLeaseLiabilityToBePaidYearFourAndFive_a5aac5b2-9314-4bab-95c2-84c394619b76" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.htgc.com/role/CommitmentsandContingenciesScheduleofFutureMinimumLeasePaymentsUnderOperatingLeasesandReconciliationtoOperatingLeaseLiabilityDetails" xlink:type="simple" xlink:href="htgc-20260331.xsd#CommitmentsandContingenciesScheduleofFutureMinimumLeasePaymentsUnderOperatingLeasesandReconciliationtoOperatingLeaseLiabilityDetails"/>
  <link:calculationLink xlink:role="http://www.htgc.com/role/CommitmentsandContingenciesScheduleofFutureMinimumLeasePaymentsUnderOperatingLeasesandReconciliationtoOperatingLeaseLiabilityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_223405b5-63e1-4daf-af76-11a11f11158c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiability_be34ee01-ccb5-434b-add0-243e2e221cd2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiability"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_223405b5-63e1-4daf-af76-11a11f11158c" xlink:to="loc_us-gaap_OperatingLeaseLiability_be34ee01-ccb5-434b-add0-243e2e221cd2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_1e7cfbb3-7796-4244-b9a8-63a030422176" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_223405b5-63e1-4daf-af76-11a11f11158c" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_1e7cfbb3-7796-4244-b9a8-63a030422176" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.htgc.com/role/CommitmentsandContingenciesScheduleofFutureMinimumLeasePaymentsUnderOperatingLeasesandReconciliationtoOperatingLeaseLiabilityDetails_1" xlink:type="simple" xlink:href="htgc-20260331.xsd#CommitmentsandContingenciesScheduleofFutureMinimumLeasePaymentsUnderOperatingLeasesandReconciliationtoOperatingLeaseLiabilityDetails_1"/>
  <link:calculationLink xlink:role="http://www.htgc.com/role/CommitmentsandContingenciesScheduleofFutureMinimumLeasePaymentsUnderOperatingLeasesandReconciliationtoOperatingLeaseLiabilityDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_3bf27c90-e033-450d-9f80-8ed92a4fc383" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_4ce9d2fb-d3f2-4539-81ca-010baabe1379" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_3bf27c90-e033-450d-9f80-8ed92a4fc383" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_4ce9d2fb-d3f2-4539-81ca-010baabe1379" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_17914012-2ade-4624-8a4e-864f2ade3197" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_3bf27c90-e033-450d-9f80-8ed92a4fc383" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_17914012-2ade-4624-8a4e-864f2ade3197" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_dd032ae1-34ab-42f8-80f6-dafc48aec0b3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_3bf27c90-e033-450d-9f80-8ed92a4fc383" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_dd032ae1-34ab-42f8-80f6-dafc48aec0b3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_27ed49c7-6a47-4c03-a784-4c02b8bd5634" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_3bf27c90-e033-450d-9f80-8ed92a4fc383" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_27ed49c7-6a47-4c03-a784-4c02b8bd5634" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_htgc_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearThree_6cf86468-149a-463f-a8a3-d5d91daf3326" xlink:href="htgc-20260331.xsd#htgc_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearThree"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_3bf27c90-e033-450d-9f80-8ed92a4fc383" xlink:to="loc_htgc_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearThree_6cf86468-149a-463f-a8a3-d5d91daf3326" xlink:type="arc"/>
  </link:calculationLink>
</link:linkbase>
