The HTML <sub> element defines a span of text that should be displayed, for typographic reasons, lower, and often smaller, than the main span of text.
| Content categories | Flow content and phrasing content |
|---|---|
| Permitted content | Phrasing content |
| Tag omission | None, both the starting and ending tag are mandatory. |
| Permitted parents | Any element that can contain phrasing content |
| Permitted ARIA roles | Any |
| DOM Interface | HTMLElement |
Attributes
This element only includes the global attributes.
Usage notes
- This element should be used for typographical reasons only, i.e. changing the position of the text changing its meaning like in mathematical (like t2, though the use of a MathML formula should be considered) or chemical formulas (like
H2O). - This element must not be used for styling purpose like the styling of the product name Latex. In that case CSS style should be used: the
vertical-alignproperty with thesubvalue will achieve the same effect.
Examples
<p>The chemical formula of water: H<sub>2</sub>O</p>
Result
The chemical formula of water: H2O
Specifications
| Specification | Status | Comment |
|---|---|---|
| WHATWG HTML Living Standard The definition of '<sub> and <sup>' in that specification. |
Living Standard | Â |
| HTML5 The definition of '<sub> and <sup>;' in that specification. |
Recommendation | Â |
See also
- The
<sup>HTML element that produces superscript. Note that you cannot use them both at the same time and you need to use MathML to produce both a superscript and a subscript next to the chemical symbol of an element, representing its atomic number and its nuclear number. - The
<msub>,<msup>, and<msubsup>MathML elements.