Auto-render extension

This is an extension to automatically render all of the math inside of text. It searches all of the text nodes in a given element for the given delimiters, and renders the math in place.


This extension isn't part of KaTeX proper, so the script should be separately included in the page:

<script src="" integrity="sha384-dq1/gEHSxPZQ7DdrM82ID4YVol9BYyU7GbWlIwnwyPzotpoc57wDw/guX8EaYGPx" crossorigin="anonymous"></script>

Then, call the exposed renderMathInElement function in a script tag before the close body tag:


See index.html for an example.

If you prefer to have all your setup inside the html <head>, you can use the following script there (instead of the one above at the end of the <body>):

    document.addEventListener("DOMContentLoaded", function() {


This extension exposes a single function, window.renderMathInElement, with the following API:

function renderMathInElement(elem, options)

elem is an HTML DOM element. The function will recursively search for text nodes inside this element and render the math in them.

options is an optional object argument with the following keys:

  • delimiters: This is a list of delimiters to look for math. Each delimiter has three properties:

    • left: A string which starts the math expression (i.e. the left delimiter).
    • right: A string which ends the math expression (i.e. the right delimiter).
    • display: A boolean of whether the math in the expression should be rendered in display mode or not.

    The default value is:

      {left: "$$", right: "$$", display: true},
      {left: "\\[", right: "\\]", display: true},
      {left: "\\(", right: "\\)", display: false}
  • ignoredTags: This is a list of DOM node types to ignore when recursing through. The default value is ["script", "noscript", "style", "textarea", "pre", "code"].