HTML Subscript: Using sub Tags

HTML Subscript: Main Tips

• To make plain text into a subscript HTML element, you should use <sub> tags. Both starting and ending tags must be used.
• HTML subscript has a lower baseline and occupies less height than usual text.
• The <sub> tag does not have specific attributes, but supports global ones.

HTML Code for Subscript

By surrounding inline text with <sub> tags, you turn it into subscript in HTML:

<p>This text contains <sub>subscript</sub> text.</p>

HTML subscript <sub> tag uses this default CSS styling:

sub {
    vertical-align: sub;
    font-size: smaller;
}

Tip: you can learn more about these properties in CSS vertical-align and fonts tutorials.

Using Subscript in HTML

You should only use HTML subscript for typographical reasons, for example:

• footnote numbers
• variable subscripts
• chemical formulas

<!-- Here you can see footnote numbers: -->
<p>I do not like green eggs<sub>1</sub> and ham<sub>2</sub>!</p>
<!-- Here you can see variable subscripts: -->
<p>2<sub>3</sub>,  4<sub>5</sub>, x<sub>y</sub></p>
<!-- Here you can see chemical formulas: -->
<p>H<sub>2</sub>O, NaHCO<sub>3</sub>, C<sub>12</sub>H<sub>22</sub>O<sub>11</sub></p>

Tip: in other cases, use CSS styling properties.

Browser Support

Mobile Browser Support