<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0609</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2026-10-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000016058</issuerCik>
        <issuerName>CACI INTERNATIONAL INC /DE/</issuerName>
        <issuerTradingSymbol>CACI</issuerTradingSymbol>
        <issuerForeignTradingSymbol></issuerForeignTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0002040101</rptOwnerCik>
            <rptOwnerName>Weir Tracy</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerNonUSAddressFlag>false</rptOwnerNonUSAddressFlag>
            <rptOwnerStreet1>11487 SUNSET HILLS ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>RESTON</rptOwnerCity>
            <rptOwnerState>VA</rptOwnerState>
            <rptOwnerZipCode>20190</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Executive Officer, UK</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

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        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
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                </underlyingSecurityTitle>
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                </underlyingSecurityShares>
            </underlyingSecurity>
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                </underlyingSecurityTitle>
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                <equitySwapInvolved>0</equitySwapInvolved>
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                <transactionShares>
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                    <value>195</value>
                </sharesOwnedFollowingTransaction>
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                <value>Performance Restricted Stock Units</value>
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            <transactionAmounts>
                <transactionShares>
                    <value>317</value>
                </transactionShares>
                <transactionPricePerShare>
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                </underlyingSecurityTitle>
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            <transactionAmounts>
                <transactionShares>
                    <value>316</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F6"/>
                </transactionPricePerShare>
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                    <value>A</value>
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            <exerciseDate>
                <footnoteId id="F6"/>
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            <expirationDate>
                <footnoteId id="F6"/>
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            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>CACI Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>316</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
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                <sharesOwnedFollowingTransaction>
                    <value>316</value>
                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
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        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">On October 1, 2023, Ms. Weir was granted 319 performance restricted stock units. The PRSU's will vest on the third anniversary of the grant date based on the achievement of a three-year performance measure.</footnote>
        <footnote id="F2">On October 1, 2023, Ms. Weir was granted 319 restricted stock units. These restricted stock units will vest 1/3 per year for three years.</footnote>
        <footnote id="F3">On October 1, 2024, Ms. Weir was granted 262 restricted stock units. These restricted stock units will vest 1/3 per year for three years.</footnote>
        <footnote id="F4">On October 1, 2025, Ms. Weir was granted 291 restricted stock units. These restricted stock units will vest 1/3 per year for three years.</footnote>
        <footnote id="F5">On October 1, 2026, Ms. Weir was granted 317 performance restricted stock units. The PRSU's will vest on the third anniversary of the grant date based on the achievement of a three-year performance measure.</footnote>
        <footnote id="F6">On October 1, 2026, Ms. Weir was granted 316 restricted stock units. These restricted stock units will vest 1/3 per year for three years.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Tracy Weir</signatureName>
        <signatureDate>2026-10-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
