Fast math typesetting for the web.
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Latest commit 429c1f6 Apr 15, 2017 @kevinbarabash kevinbarabash committed on GitHub Merge pull request #678 from edemaine/symbols
Fix font typo math -> main
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build Add a setup rule to Makefile Jul 30, 2013
contrib/auto-render Update README files to 0.7.1 release Jan 22, 2017
dockers Serve files with and without babelify step Jan 14, 2017
metrics Migrate to eslint Dec 1, 2015
src Merge pull request #678 from edemaine/symbols Apr 16, 2017
static Support \bmod, \pmod, \pod, and \mod. Jan 1, 2017
test Merge pull request #605 from gagern/overset Apr 16, 2017
.arcconfig Fix `arc lint` Jun 26, 2015
.arclint Fix `arc lint` Jun 26, 2015
.babelrc Include babelify step in browserify calls Jan 14, 2017
.eslintrc Builtin macros, macro arguments, overset and underset Apr 5, 2017
.gitattributes Set up a diff attribute and textconv instructions for font files Jan 19, 2017
.gitignore Add build artifacts to .gitignore and allow installing dependencies w… Nov 3, 2016
.travis.yml Check out test fonts in (#570) Nov 23, 2016 Create (#553) Nov 3, 2016 Add a link to symbol/function support preview page Oct 20, 2015
LICENSE.txt Add basic auto-render extension Apr 1, 2015
Makefile Show compressed sizes correctly Jan 20, 2017 Fixed missing verb in README (#668) Mar 14, 2017
bower.json Drop version field from bower.json Jan 13, 2017
check-node-version.js Include babelify step in browserify calls Jan 14, 2017
cli.js Turn var into const or let Jan 14, 2017
katex.js Turn var into const or let Jan 14, 2017
lint_blacklist.txt Blacklist dist/** so that ka-lint doesn't barf on those files Apr 16, 2016
package.json Builtin macros, macro arguments, overset and underset Apr 5, 2017 Obtain updated README by using a checkout Jan 22, 2017
server.js Serve files with and without babelify step Jan 14, 2017
update-sri.js Update CDN version numbers and SRI hashes on release Jan 13, 2017

KaTeX Build Status

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KaTeX is a fast, easy-to-use JavaScript library for TeX math rendering on the web.

  • Fast: KaTeX renders its math synchronously and doesn't need to reflow the page. See how it compares to a competitor in this speed test.
  • Print quality: KaTeX’s layout is based on Donald Knuth’s TeX, the gold standard for math typesetting.
  • Self contained: KaTeX has no dependencies and can easily be bundled with your website resources.
  • Server side rendering: KaTeX produces the same output regardless of browser or environment, so you can pre-render expressions using Node.js and send them as plain HTML.

KaTeX supports all major browsers, including Chrome, Safari, Firefox, Opera, and IE 8 - IE 11. A list of supported commands can be found on the wiki.


You can download KaTeX and host it on your server or include the katex.min.js and katex.min.css files on your page directly from a CDN:

<link rel="stylesheet" href="" integrity="sha384-wITovz90syo1dJWVh32uuETPVEtGigN07tkttEqPv+uR2SE/mbQcG7ATL28aI9H0" crossorigin="anonymous">
<script src="" integrity="sha384-/y1Nn9+QQAipbNQWU65krzJralCnuOasHncUFXGkdwntGeSvQicrYkiUBwsgUqc1" crossorigin="anonymous"></script>

In-browser rendering

Call katex.render with a TeX expression and a DOM element to render into:

katex.render("c = \\pm\\sqrt{a^2 + b^2}", element);

If KaTeX can't parse the expression, it throws a katex.ParseError error.

Server side rendering or rendering to a string

To generate HTML on the server or to generate an HTML string of the rendered math, you can use katex.renderToString:

var html = katex.renderToString("c = \\pm\\sqrt{a^2 + b^2}");
// '<span class="katex">...</span>'

Make sure to include the CSS and font files, but there is no need to include the JavaScript. Like render, renderToString throws if it can't parse the expression.

Rendering options

You can provide an object of options as the last argument to katex.render and katex.renderToString. Available options are:

  • displayMode: boolean. If true the math will be rendered in display mode, which will put the math in display style (so \int and \sum are large, for example), and will center the math on the page on its own line. If false the math will be rendered in inline mode. (default: false)
  • throwOnError: boolean. If true, KaTeX will throw a ParseError when it encounters an unsupported command. If false, KaTeX will render the unsupported command as text in the color given by errorColor. (default: true)
  • errorColor: string. A color string given in the format "#XXX" or "#XXXXXX". This option determines the color which unsupported commands are rendered in. (default: #cc0000)
  • macros: object. A collection of custom macros. Each macro is a property with a name like \name (written "\\name" in JavaScript) which maps to a string that describes the expansion of the macro.

For example:

katex.render("c = \\pm\\sqrt{a^2 + b^2}\\in\\RR", element, {
  displayMode: true,
  macros: {
    "\\RR": "\\mathbb{R}"

Automatic rendering of math on a page

Math on the page can be automatically rendered using the auto-render extension. See the Auto-render README for more information.




KaTeX is licensed under the MIT License.