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        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001953926</identifier>
        </entity>
        <period>
            <startDate>2026-09-10</startDate>
            <endDate>2026-09-10</endDate>
        </period>
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    <context id="offrl_1">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001953926</identifier>
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            <startDate>2026-09-10</startDate>
            <endDate>2026-09-10</endDate>
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        <measure>iso4217:USD</measure>
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    <unit id="pure">
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    <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">0001953926</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-172">Zenas BioPharma, Inc.</dei:EntityRegistrantName>
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    <ffd:OfferingSctyTp contextRef="offrl_1" id="ixv-202">Equity</ffd:OfferingSctyTp>
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      unitRef="Shares">600000</ffd:AmtSctiesRegd>
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      contextRef="offrl_1"
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      contextRef="offrl_1"
      decimals="2"
      id="ixv-207"
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      contextRef="offrl_1"
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      decimals="2"
      id="ixv-209"
      unitRef="USD">2718.64</ffd:FeeAmt>
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    <ffd:TtlFeeAmt contextRef="rc" decimals="2" id="ixv-211" unitRef="USD">2718.64</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">2718.64</ffd:NetFeeAmt>
    <ffd:OfferingNote contextRef="offrl_1" id="ixv-214">1(a) Pursuant to Rule 416(a) promulgated under the Securities Act, this Registration Statement also covers such additional shares of the Registrant's Common Stock as may be issued to prevent dilution from stock splits, stock dividends and similar transactions.

1(b) Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(c) and 457(h) under the Securities Act. The proposed maximum offering price per share and the proposed maximum aggregate offering price are based upon the average of the high and low sale price of the Registrant's Common Stock, as reported by the Nasdaq Global Select Market on September 9, 2026, which were $33.53 and $32.08, respectively.
</ffd:OfferingNote>
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