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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-02-19</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001365916</issuerCik>
        <issuerName>AMYRIS, INC.</issuerName>
        <issuerTradingSymbol>AMRS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001032455</rptOwnerCik>
            <rptOwnerName>DOERR L JOHN</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O AMYRIS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>5885 HOLLIS STREET, SUITE 100</rptOwnerStreet2>
            <rptOwnerCity>EMERYVILLE</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94608</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2020-02-19</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>52785</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>3.41</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>53263647</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Foris Ventures, LLC</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7798</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>9648</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Clarus, LLC</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>248304</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Kleiner Perkins Caufield &amp; Byers XII, LLC</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4531</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By KPCB XII Founders Fund, LLC</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>567</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By The Vallejo Ventures Trust U/T/A 2/12/96</value>
                    <footnoteId id="F5"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The Reporting Person indirectly holds all of the membership interests in Foris Ventures, LLC. The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein.</footnote>
        <footnote id="F2">The Reporting Person is the manager of Clarus, LLC. The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein. The shares are held for convenience in the name of &quot;KPCB Holdings, Inc., as nominee&quot; for the account of entities affiliated with Kleiner Perkins Caufield &amp; Byers and others. KPCB Holdings, Inc. has no voting, dispositive or pecuniary interest in any such shares.</footnote>
        <footnote id="F3">The Managing Member of Kleiner Perkins Caufield &amp; Byers XII, LLC is KPCB XII Associates, LLC, of which the Reporting Person is the managing member. The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein.The shares are held for convenience in the name of &quot;KPCB Holdings, Inc., as nominee&quot; for the account of entities affiliated with Kleiner Perkins Caufield &amp; Byers and others. KPCB Holdings, Inc. has no voting, dispositive or pecuniary interest in any such shares.</footnote>
        <footnote id="F4">The Managing Member of KPCB XII Founders Fund, LLC is KPCB XII Associates, LLC, of which the Reporting Person is the managing member. The Reporting Person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein.The shares are held for convenience in the name of &quot;KPCB Holdings, Inc., as nominee&quot; for the account of entities affiliated with Kleiner Perkins Caufield &amp; Byers and others. KPCB Holdings, Inc. has no voting, dispositive or pecuniary interest in any such shares.</footnote>
        <footnote id="F5">The Reporting Person is a Trustee of The Vallejo Ventures Trust U/T/A 2/12/96.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>L. John Doerr, by Bruna Lawant, Attorney-in-Fact</signatureName>
        <signatureDate>2020-02-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
