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Home Help: <sub> element

The <sub> Element

Inline Text Semantics

Use <sub> to markup subscript. Subscript text is rendered below and immediately to one side of another character. Use <sub> to convey a specific meaning; don't use it solely for presentation's sake.

Attributes for <sub>
TypeAttribute List
'Standard' Attributes(none)
New HTML5 Attributes"popover"


  • Consider MathML for mathematical expressions with subscripts and superscripts.

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Accessibility Information & Tips

  • Use semantic markup elements like <em>, <strong>, <cite>, <blockquote>, <q>, <quote>, <sub>, and <sup> when appropriate. Use <em> and <strong> to indicate structural emphasis, use <blockquote> for long quotations which may require paragraph breaks, use <q> for short inline quotations, and use <sub> and <sup> for subscripts and superscripts. Visit https://www.w3.org/TR/WCAG20-TECHS/H49 for more information.

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