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

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2025-06-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000101984</issuerCik>
        <issuerName>UNIVERSAL ELECTRONICS INC</issuerName>
        <issuerTradingSymbol>UEIC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001443284</rptOwnerCik>
            <rptOwnerName>Singer Eric</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O IMMERSION CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>2999 NE 191ST ST, STE 610</rptOwnerStreet2>
            <rptOwnerCity>AVENTURA</rptOwnerCity>
            <rptOwnerState>FL</rptOwnerState>
            <rptOwnerZipCode>33180</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-06-02</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2025-06-02</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.6799</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>53407</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-06-02</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2025-06-02</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>3000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.675</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>56407</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-06-02</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2025-06-02</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>634</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.662</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>57041</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-06-02</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2025-06-02</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>56</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.52</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>57097</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-06-03</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2025-06-03</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>4000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.62</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>61097</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-06-03</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2025-06-03</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>200</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.70</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>61297</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1544647</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F3"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Group</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F4"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F5"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F5"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1250</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1250</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">This represents the weighted average purchase price of the shares acquired. The purchase prices ranged from $6.66 to $6.68.</footnote>
        <footnote id="F2">This represents the weighted average purchase price of the shares acquired. The purchase prices ranged from $6.5115 to $6.53.</footnote>
        <footnote id="F3">Shares of the Issuer's Common Stock owned directly by Toro 18. Immersion, as the sole member of Toro 18, may be deemed to beneficially own the shares owned directly by Toro 18. Mr. Martin, as the Chief Strategy Officer of Toro 18, may be deemed to beneficially own the shares owned directly by Toro 18. Mr. Singer, as the President and Chief Executive Officer of Toro 18, may be deemed to beneficially own the securities owned directly by Toro 18.</footnote>
        <footnote id="F4">Each restricted stock unit represents a contingent right to receive one share of UEI common stock.</footnote>
        <footnote id="F5">The restricted stock units vest in accordance with the vesting schedule of each RSU grant.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/Eric Singer by Bryan Allison, pursuant to Limited Power of Attorney dated June 24, 2024</signatureName>
        <signatureDate>2025-06-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
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X0508
4
2025-06-02
0
0000101984
UNIVERSAL ELECTRONICS INC
UEIC
0001443284
Singer Eric
C/O IMMERSION CORPORATION
2999 NE 191ST ST, STE 610
AVENTURA
FL
33180
1
0
1
0
0
Common Stock
2025-06-02
2025-06-02
4
P
0
1000
6.6799
A
53407
D
Common Stock
2025-06-02
2025-06-02
4
P
0
3000
6.675
A
56407
D
Common Stock
2025-06-02
2025-06-02
4
P
0
634
6.662
A
57041
D
Common Stock
2025-06-02
2025-06-02
4
P
0
56
6.52
A
57097
D
Common Stock
2025-06-03
2025-06-03
4
P
0
4000
6.62
A
61097
D
Common Stock
2025-06-03
2025-06-03
4
P
0
200
6.70
A
61297
D
Common Stock
1544647
I
By Group
Restricted Stock Units
Common Stock
1250
1250
D
This represents the weighted average purchase price of the shares acquired. The purchase prices ranged from $6.66 to $6.68.
This represents the weighted average purchase price of the shares acquired. The purchase prices ranged from $6.5115 to $6.53.
Shares of the Issuer's Common Stock owned directly by Toro 18. Immersion, as the sole member of Toro 18, may be deemed to beneficially own the shares owned directly by Toro 18. Mr. Martin, as the Chief Strategy Officer of Toro 18, may be deemed to beneficially own the shares owned directly by Toro 18. Mr. Singer, as the President and Chief Executive Officer of Toro 18, may be deemed to beneficially own the securities owned directly by Toro 18.
Each restricted stock unit represents a contingent right to receive one share of UEI common stock.
The restricted stock units vest in accordance with the vesting schedule of each RSU grant.
/s/Eric Singer by Bryan Allison, pursuant to Limited Power of Attorney dated June 24, 2024
2025-06-03