href

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Non-standard: This feature is not standardized. We do not recommend using non-standard features in production, as they have limited browser support, and may change or be removed. However, they can be a suitable alternative in specific cases where no standard option exists.

Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

The href global attribute creates a hyperlink on the MathML element pointing to the specified URL.

Warning: Setting href on MathML elements other than <a> is deprecated. Use the <a> element to create hyperlinks within MathML content instead, as defined in the MathML Core specification.

Example

The first equation links to the Wikipedia article about the mass-energy equivalence. The square root part of the second equation is a link to the SageMath calculation.

Note: You should avoid nesting MathML elements with the href attributes, just like <a> elements, as is will lead to user confusion and accessibility issues.

html,
body {
  height: 100%;
}

body {
  display: grid;
  place-items: center;
  font-size: 1.5rem;
}

html

<math
  display="block"
  href="https://en.wikipedia.org/wiki/Mass-energy_equivalence">
  <mrow>
    <mi>E</mi>
    <mo>=</mo>
    <mi>m</mi>
    <msup>
      <mi>c</mi>
      <mn>2</mn>
    </msup>
  </mrow>
</math>

<math display="block">
  <mi>c</mi>
  <mo>=</mo>
  <msqrt href="https://sagecell.sagemath.org/?z=eJwrLiwq0TCOM9I2iTPSBAAeqgPO">
    <msup>
      <mn>3</mn>
      <mn>2</mn>
    </msup>
    <mo>+</mo>
    <msup>
      <mn>4</mn>
      <mn>2</mn>
    </msup>
  </msqrt>
  <mo>=</mo>
  <mn>5</mn>
</math>