APLD: Zhang Jason Gechen reported buying shares

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

    <schemaVersion>X0609</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2026-10-16</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001144879</issuerCik>
        <issuerName>Applied Digital Corp.</issuerName>
        <issuerTradingSymbol>APLD</issuerTradingSymbol>
        <issuerForeignTradingSymbol></issuerForeignTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001900445</rptOwnerCik>
            <rptOwnerName>Zhang Jason Gechen</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerNonUSAddressFlag>false</rptOwnerNonUSAddressFlag>
            <rptOwnerStreet1>3811 TURTLE CREEK BOULEVARD</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 2100</rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75219</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2026-10-16</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>300000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>18.86</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2839227</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Constitutes the weighted average purchase price for multiple transactions reported on this line having prices per share ranging from $18.40 to $19.16. The Reporting Person will provide upon request by the Commission staff, the issuer or a security holder of the issuer, full information regarding each separate transaction.</footnote>
        <footnote id="F2">Includes 500,000 RSU's granted on February 6, 2026 (the &quot;Grant Date&quot;) represent a contingent right to receive shares of common stock of Applied Digital Corporation (the &quot;Company&quot;) on a one-for-one basis, have no expiration date, and vest as follows: 100,000 RSUs on February 6, 2027 (the &quot;Cliff Date&quot;) with the remainder vesting in equal installments of 50,000 RSUs every six months every six months after the Cliff Date, such that the RSUs will be fully vested on the five-year anniversary of the Grant Date, each such vesting subject to the Reporting Person's continued full-time employment with the Company in a role approved by the Board of Directors of the Company through the applicable vesting date or accelerated vesting upon certain conditions.</footnote>
        <footnote id="F3">Includes the remainder of 750,000 RSUs granted on August 8, 2025. The RSUs represent a contingent right to receive shares of common stock of the Company on a one-for-one basis and have no expiration date. 125,000 of the RSUs shall vest on each of March 12, 2027, September 12, 2027 and March 12, 2028, each such vesting subject to the Reporting Person's continued full-time employment with the Company in a role approved by the Board of Directors of the Company through the applicable date or accelerated vesting upon certain conditions.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Mark Chavez as Attorney-in-Fact</signatureName>
        <signatureDate>2026-10-19</signatureDate>
    </ownerSignature>
</ownershipDocument>