The HTML Subscript Element (
<sub>) defines a span of text that should be displayed, for typographic reasons, lower, and often smaller, than the main span of text.
- 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 the
subvalue will achieve the same effect.
|Content categories||Flow content and phrasing content|
|Permitted content||Phrasing content|
|Tag omission||None as both the start and end tag are mandatory|
|Permitted parent elements||Any element that can contain phrasing content|
|Normative document||HTML5, section 4.6.14 (HTML4.01, section 9.2.3)|
This element only includes the global attributes.
This element implements the
Implementation note: up to Gecko 1.9.2 inclusive, Firefox implements the HTMLSpanElement interface for this element.
<p>The chemical formula of water is H<sub>2</sub>O</p>
The chemical formula of water is H2O
<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.