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      xlink:href="https://xbrl.sec.gov/ffd/2026/ffd-2026.xsd"
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        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0000729580</identifier>
        </entity>
        <period>
            <startDate>2026-09-01</startDate>
            <endDate>2026-09-01</endDate>
        </period>
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    <context id="offrl_1">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0000729580</identifier>
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        <period>
            <startDate>2026-09-01</startDate>
            <endDate>2026-09-01</endDate>
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    <unit id="USD">
        <measure>iso4217:USD</measure>
    </unit>
    <unit id="pure">
        <measure>pure</measure>
    </unit>
    <unit id="Shares">
        <measure>shares</measure>
    </unit>
    <ffd:FormTp contextRef="rc" id="ixv-168">S-8</ffd:FormTp>
    <ffd:SubmissnTp contextRef="rc" id="ixv-169">S-8</ffd:SubmissnTp>
    <ffd:FeeExhibitTp contextRef="rc" id="ixv-170">EX-FILING FEES</ffd:FeeExhibitTp>
    <dei:EntityCentralIndexKey contextRef="rc" id="ixv-171">0000729580</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-172">BEL FUSE INC /NJ</dei:EntityRegistrantName>
    <ffd:OfferingTableNa contextRef="rc" id="hiddenrcOfferingTableNa" xsi:nil="true"/>
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    <ffd:FormTp contextRef="rc" id="ixv-200">S-8</ffd:FormTp>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-201">BEL FUSE INC /NJ</dei:EntityRegistrantName>
    <ffd:OfferingSctyTp contextRef="offrl_1" id="ixv-202">Equity</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="offrl_1" id="ixv-203">Class B Common stock, par value $0.10 per share</ffd:OfferingSctyTitl>
    <ffd:FeesOthrRuleFlg contextRef="offrl_1" id="ixv-204">true</ffd:FeesOthrRuleFlg>
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      id="ixv-205"
      unitRef="Shares">725000</ffd:AmtSctiesRegd>
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      contextRef="offrl_1"
      decimals="2"
      id="ixv-206"
      unitRef="USD">252.77</ffd:MaxOfferingPricPerScty>
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      contextRef="offrl_1"
      decimals="2"
      id="ixv-207"
      unitRef="USD">183258250.00</ffd:MaxAggtOfferingPric>
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      contextRef="offrl_1"
      decimals="7"
      id="ixv-208"
      unitRef="pure">0.0001381</ffd:FeeRate>
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      contextRef="offrl_1"
      decimals="2"
      id="ixv-209"
      unitRef="USD">25307.96</ffd:FeeAmt>
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    <ffd:TtlFeeAmt contextRef="rc" decimals="2" id="ixv-211" unitRef="USD">25307.96</ffd:TtlFeeAmt>
    <ffd:TtlOffsetAmt contextRef="rc" decimals="2" id="ixv-212" unitRef="USD">0.00</ffd:TtlOffsetAmt>
    <ffd:NetFeeAmt contextRef="rc" decimals="2" id="ixv-213" unitRef="USD">25307.96</ffd:NetFeeAmt>
    <ffd:OfferingNote contextRef="offrl_1" id="ixv-214">Pursuant to Rule 416(a) under the Securities Act of 1933, as amended (the "Securities Act"), this registration statement shall also cover any additional shares of the Registrant's Class B common stock, par value $0.10 per share ("Class B Common Stock"), that may become issuable under the terms of the Bel Fuse Inc. 2026 Equity Compensation Plan (the "2026 Plan") by reason of any share split, share dividend, recapitalization or other similar transaction effected without the Registrant's receipt of consideration which results in an increase in the number of the outstanding shares of Class B Common Stock. 2. Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(c) and (h) under the Securities Act, based on the average of the high and low sales prices of the Class B Common Stock on the Nasdaq Global Select Market on August 28, 2026. 3. Represents shares available for issuance under the 2026 Plan. For more information, see the "Explanatory Note" to this registration statement on Form S-8. 4. The Registrant does not have any fee offsets to claim.

2. Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(c) and (h) under the Securities Act, based on the average of the high and low sales prices of the Class B Common Stock on the Nasdaq Global Select Market on August 24, 2026.

3. Represents shares available for issuance under the 2026 Plan. For more information, see the "Explanatory Note" to this registration statement on Form S-8.

4. The Registrant does not have any fee offsets to claim.</ffd:OfferingNote>
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