HTML <sup> tag

The <sup> tag is used to define a superscript text, which appears half a character above the regular line and is rendered smaller than the rest of the text. The tag is commonly used to define footnotes and formulas.

You must use the <sup> tag only for typographical reasons. It shouldn’t be used for styling purposes. If you want to change the vertical position of a text, you can use the CSS vertical-align property with the "super" value.

The <sub> tag is used to define the subscript.

Here are some use cases for a <sup> element:

  • Representing superior lettering used in some languages when rendering specific abbreviations.
  • Representing exponents (e.g. "x2.").
  • Representing ordinal numbers (e.g. "5th" instead of "fifth").

Syntax

The <sup> tag comes in pairs. The content is written between the opening (<sup>) and closing (</sup>) tags.

Example of the HTML <sup> tag:

<!DOCTYPE html>
<html>
  <head>
    <title>Title of the document</title>
  </head>
  <body>
    <p>
      E = mc<sup>2</sup>, where E is the energy of the object, m is the weight, c is the light speed in vacuum.
    </p>
  </body>
</html>

Result

 sup example

Example of the HTML <sup> tag used with the CSS vertical-align property:

<!DOCTYPE html>
<html>
  <head>
    <title>Title of the document</title>
    <style>
      sup {
        vertical-align: sup;
        font-size: medium;
      }
    </style>
  </head>
  <body>
    <h1>Example of the sub tag</h1>
    <p>
      Here is some text <sup> with the sup tag</sup>.
    </p>
    <p>
      Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis ...
    </p>
    <p>
      Reference site about Lorem Ipsum,
      <sup> giving information on its origins</sup>, as well as a random Lipsum generator.
    </p>
  </body>
</html>

Example of the HTML <sup> tag used with the <sub> tag:

<!DOCTYPE html>
<html>
  <head>
    <title>Title of the document</title>
    <style>
      sup {
        vertical-align: sup;
        font-size: medium;
      }
      
      sub {
        vertical-align: sub;
        font-size: small;
      }
    </style>
  </head>
  <body>
    <h1>Example of the sub tag</h1>
    <p>
      Here is some text
      <sub> with the sup tag</sub>.
    </p>
    <p>
      Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis ...
    </p>
    <p>
      Reference site about Lorem Ipsum,
      <sup> giving information on its origins</sup>, as well as a random Lipsum generator.</p>
  </body>
</html>

Attributes

The <sup> tag supports Global attributes and the Event Attributes.

How to style <sup> tag?

Common properties to alter the visual weight/emphasis/size of text in <sup> tag:

  • CSS font-style property sets the style of the font. normal | italic | oblique | initial | inherit.
  • CSS font-family property specifies a prioritized list of one or more font family names and/or generic family names for the selected element.
  • CSS font-size property sets the size of the font.
  • CSS font-weight property defines whether the font should be bold or thick.
  • CSS text-transform property controls text case and capitalization.
  • CSS text-decoration property specifies the decoration added to text, and is a shorthand property for text-decoration-line, text-decoration-color, text-decoration-style.

Coloring text in <sup> tag:

  • CSS color property describes the color of the text content and text decorations.
  • CSS background-color property sets the background color of an element.

Text layout styles for <sup> tag:

  • CSS text-indent property specifies the indentation of the first line in a text block.
  • CSS text-overflow property specifies how overflowed content that is not displayed should be signalled to the user.
  • CSS white-space property specifies how white-space inside an element is handled.
  • CSS word-break property specifies where the lines should be broken.

Other properties worth looking at for <sup> tag:

Browser support

chrome edge firefox safari opera

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