The <sub> tag is used to display text as subscript.
Subscript is text that is smaller and appears lower than regular text.
A <sub> element that displays a subscripted number 2.
The formula for water is H2O.
<p>
The formula for water is H<sub>2</sub>O.
</p>
sub = subscript
The <sub> tag is used to display text as subscript.
Subscript text is half a character below the baseline and it uses smaller font.
The <sub> element can be used to write chemical or mathematical formulas.
With just <sup> and <sub>,
complex chemical formulas can be written.
The formula for Hexamminecobalt chloride is [Co(NH3)6]3+Cl3−
<p>
The formula for Hexamminecobalt chloride is
[Co(NH<sub>3</sub>)<sub>6</sub>]<sup>3+</sup>Cl<sup>3−</sup>
</p>
The <sub> element has no attributes, but it does accept global attributes.
The following are commonly used.
| Attribute | Value | Description |
|---|---|---|
| id | value | Provides the sub element with a unique identifier. |
| class | classnames | Assigns one or more classnames to the sub element. |
| style | CSS-values | Assigns CSS style values to the sub element. |
For additional global attributes see our global attributes list.
The <sub> tag is part of a group of tags
that are used to create and format text documents.
This group is referred to as the Text tag group.
Together, they allow you to create comprehensive HTML text documents.
Here is a list of text tags.
| Element | Description |
|---|---|
| <h1>-<h6> | Defines text headings in 6 different sizes |
| <p> | Creates a paragraph |
| <span> | Container for one or more inline text elements |
| <br> | Creates a line break |
| <sup> | Specifies superscript text |
| <sub> | Specifies subscripted text |
| <u> | Specifies underlined text |
| <i> | Specifies italic text |
| <b> | Specifies bold text |
| <em> | Marks text that needs emphasis |
| <strong> | Indicates text that is important or with high urgency |
| <del> | Defines deleted text |
| <ins> | Defines inserted text |
| <ruby> | Represents a small annotation with pronunciation of text |
| <kbd> | Specifies keyboard input, such as, CTRL or ALT |
| <wbr> | Specifies a preferred word-break location for long words |
Here is when <sub> support started for each browser:
 Chrome
|
1.0 | Sep 2008 |
 Firefox
|
1.0 | Sep 2002 |
 IE/Edge
|
1.0 | Aug 1995 |
 Opera
|
1.0 | Jan 2006 |
 Safari
|
1.0 | Jan 2003 |
