README.md
1# [<img src="https://khan.github.io/KaTeX/katex-logo.svg" width="130" alt="KaTeX">](https://khan.github.io/KaTeX/) [![Build Status](https://travis-ci.org/Khan/KaTeX.svg?branch=master)](https://travis-ci.org/Khan/KaTeX)
2
3[![Join the chat at https://gitter.im/Khan/KaTeX](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/Khan/KaTeX?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
4
5KaTeX is a fast, easy-to-use JavaScript library for TeX math rendering on the web.
6
7 * **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](http://jsperf.com/katex-vs-mathjax/).
8 * **Print quality:** KaTeX’s layout is based on Donald Knuth’s TeX, the gold standard for math typesetting.
9 * **Self contained:** KaTeX has no dependencies and can easily be bundled with your website resources.
10 * **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.
11
12KaTeX supports all major browsers, including Chrome, Safari, Firefox, Opera, and IE 8 - IE 11. A list of supported commands can be on the [wiki](https://github.com/Khan/KaTeX/wiki/Function-Support-in-KaTeX).
13
14## Usage
15
16You can [download KaTeX](https://github.com/khan/katex/releases) and host it on your server or include the `katex.min.js` and `katex.min.css` files on your page directly from a CDN:
17
18```html
19<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/KaTeX/0.6.0/katex.min.css">
20<script src="https://cdnjs.cloudflare.com/ajax/libs/KaTeX/0.6.0/katex.min.js"></script>
21```
22
23#### In-browser rendering
24
25Call `katex.render` with a TeX expression and a DOM element to render into:
26
27```js
28katex.render("c = \\pm\\sqrt{a^2 + b^2}", element);
29```
30
31If KaTeX can't parse the expression, it throws a `katex.ParseError` error.
32
33#### Server side rendering or rendering to a string
34
35To generate HTML on the server or to generate an HTML string of the rendered math, you can use `katex.renderToString`:
36
37```js
38var html = katex.renderToString("c = \\pm\\sqrt{a^2 + b^2}");
39// '<span class="katex">...</span>'
40```
41
42Make 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.
43
44#### Rendering options
45
46You can provide an object of options as the last argument to `katex.render` and `katex.renderToString`. Available options are:
47
48- `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`)
49- `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`)
50- `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`)
51
52For example:
53
54```js
55katex.render("c = \\pm\\sqrt{a^2 + b^2}", element, { displayMode: true });
56```
57
58#### Automatic rendering of math on a page
59
60Math on the page can be automatically rendered using the auto-render extension. See [the Auto-render README](contrib/auto-render/README.md) for more information.
61
62## Contributing
63
64See [CONTRIBUTING.md](CONTRIBUTING.md)
65
66## License
67
68KaTeX is licensed under the [MIT License](http://opensource.org/licenses/MIT).
69