<msub>

The MathML <msub> element is used to attach a subscript to an expression.
It uses the following syntax: <msub> base subscript </msub>.

Attributes

class, id, style: Provided for use with stylesheets.
href: Used to set a hyperlink to a specified URI.
mathbackground: The background color. You can use #rgb, #rrggbb and HTML color names.
mathcolor: The text color. You can use #rgb, #rrggbb and HTML color names.
subscriptshift: The minimum space by which to shift the subscript below the baseline of the expression, as a length value.

Sample rendering:

Rendering in your browser: $X_{1}$

<math>

  <msub>
    <mi>X</mi>
    <mn>1</mn>
  </msub> 

</math>

Specification	Status	Comment
MathML 3.0 The definition of 'msub' in that specification.	Recommendation	Current specification
MathML 2.0 The definition of 'msub' in that specification.	Recommendation	Initial specification

Feature	Chrome	Firefox (Gecko)	Internet Explorer	Opera	Safari
Basic support	Not supported	1.0 (1.7 or earlier)	Not supported	Not supported	5.1
`href`	Not supported	7.0 (7.0)	Not supported	Not supported	Not supported
`mathbackground`	Not supported	4.0 (2.0)	Not supported	Not supported	5.1
`mathcolor`	Not supported	4.0 (2.0)	Not supported	Not supported	5.1
`subscriptshift`	Not supported	1.0 (1.7 or earlier)	Not supported	Not supported	Not supported

Feature	Android	Chrome for Android	Firefox Mobile (Gecko)	IE Mobile	Opera Mobile	Safari Mobile
Basic support	Not supported	Not supported	1.0 (1.0)	Not supported	Not supported	Not supported
`href`	Not supported	Not supported	7.0 (7.0)	Not supported	Not supported	Not supported
`mathbackground`	Not supported	Not supported	4.0 (2.0)	Not supported	Not supported	Not supported
`mathcolor`	Not supported	Not supported	4.0 (2.0)	Not supported	Not supported	Not supported
`subscriptshift`	Not supported	Not supported	1.0 (1.0)	Not supported	Not supported	Not supported

Starting with Gecko 26.0 (Firefox 26 / Thunderbird 26 / SeaMonkey 2.23 / Firefox OS 1.2) it is no longer possible to use <none /> as a child element. The rendering has been made more consistent with equivalent configurations of <msup> and <mmultiscripts> and a bug with an incorrect application of the superscriptshift attribute has been fixed (see bug 827713 for details).