<sup>: the "Superscript" element

The HTML <sup> element specifies inline text that should be displayed as a superscript for typographical reasons only. Superscripts are typically displayed with a raised baseline using smaller text.

Usage notes

The <sup> element should be used only for typographical purposes, that is, to change the position of text to conform to typographical conventions or standards, rather than solely for presentation or appearance purposes.

For example, to style a company or product's wordmark that uses a raised baseline, you would use CSS (most likely vertical-align) instead of <sup>. This would be done using, for example, vertical-align: super or, to move the baseline up by 50%, vertical-align: 50%.

Appropriate use cases to include <sup> (but are not necessarily limited to):

  • Displaying exponents, such as "x3."
  • Displaying supercharacters, used in some languages when rendering certain abbreviations.
  • Representation of ordinal numbers, such as "4th" instead of "fourth".

Examples

Exponents

Exponents, or powers of a number, are among the most common uses of superscript text. For example:

<p>Una delle equazioni più comuni in fisica è
<var>E</var>=<var>m</var><var>c</var><sup>2</sup></p>

Ordinal numbers

Ordinal numbers, such as "fourth" in English or "fifth" in Spanish, can be abbreviated using numerals and language-specific text rendered in superscript:

<p>Il numero ordinale "quinto" può essere abbreviato nelle
varie lingue in questo modo:</p>
<ul>
  <li>Inglese: 5<sup>th</sup></li>
  <li>Francese: 5<sup>ème</sup></li>
</ul>