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

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2026-02-03</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001859392</issuerCik>
        <issuerName>Galaxy Digital Inc.</issuerName>
        <issuerTradingSymbol>GLXY</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0002052994</rptOwnerCik>
            <rptOwnerName>Paquette Anthony</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O GALAXY DIGITAL INC.</rptOwnerStreet1>
            <rptOwnerStreet2>300 VESEY STREET</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10282</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Financial Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2026-02-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>97497</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>430777</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Represents 97,497 shares of Class A common stock issuable upon the vesting of restricted stock units (&quot;RSUs&quot;).</footnote>
        <footnote id="F2">Each RSU represents the right to receive one share of the Company's Class A common stock.</footnote>
        <footnote id="F3">Includes (i) 281,250 shares of Class A common stock to be delivered in settlement of an RSU award where 93,750 RSUs are scheduled to vest on December 26, 2026, 93,750 RSUs are scheduled to vest on December 26, 2027 and 93,750 RSUs are scheduled to vest on December 26, 2028 and (ii) 97,497 shares of Class A common stock to be delivered in settlement of an RSU award where 32,174 RSUs are schedule to vest on March 1, 2027, with the remainder vesting in eight equal quarterly installments thereafter.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Frances Fuqua, Attorney-in-Fact for Anthony Paquette</signatureName>
        <signatureDate>2026-02-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
