# [](https://khan.github.io/KaTeX/)
[](https://www.npmjs.com/package/katex)
[](https://circleci.com/gh/Khan/KaTeX)
[](https://codecov.io/gh/Khan/KaTeX)
[](https://gitter.im/Khan/KaTeX?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge) [](https://greenkeeper.io/)
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](http://www.intmath.com/cg5/katex-mathjax-comparison.php).
* **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 is compatible with all major browsers, including Chrome, Safari, Firefox, Opera, Edge, and IE 9–11.
KaTeX supports much (but not all) of LaTeX and many LaTeX packages. See the [list of supported functions](https://khan.github.io/KaTeX/docs/supported.html).
## Getting started
[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:
```html
```
#### In-browser rendering
Call `katex.render` with a TeX expression and a DOM element to render into:
```js
katex.render("c = \\pm\\sqrt{a^2 + b^2}", element);
```
If KaTeX can't parse the expression, it throws a `katex.ParseError` error.
#### Rendering expressions in text elements
To automatically render math in text elements, include the [auto-render script](https://khan.github.io/KaTeX/docs/autorender.html) `contrib/auto-render.min.js`, or via CDN:
```html
````
Then, call the `renderMathInElement` function with a DOM element containing expressions in a script tag before the closing body tag:
```html
...
```
See [Auto-render Extension](https://khan.github.io/KaTeX/docs/autorender.html) for more details.
#### 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`:
```js
var html = katex.renderToString("c = \\pm\\sqrt{a^2 + b^2}");
// '...'
```
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.
## Documentation
Learn more about using KaTeX [on the website](https://khan.github.io/KaTeX)!
## Contributing
See [CONTRIBUTING.md](CONTRIBUTING.md)
## License
KaTeX is licensed under the [MIT License](http://opensource.org/licenses/MIT).
](https://khan.github.io/KaTeX/)
[](https://www.npmjs.com/package/katex)
[](https://circleci.com/gh/Khan/KaTeX)
[](https://codecov.io/gh/Khan/KaTeX)
[](https://gitter.im/Khan/KaTeX?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge) [](https://greenkeeper.io/)
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](http://www.intmath.com/cg5/katex-mathjax-comparison.php).
* **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 is compatible with all major browsers, including Chrome, Safari, Firefox, Opera, Edge, and IE 9–11.
KaTeX supports much (but not all) of LaTeX and many LaTeX packages. See the [list of supported functions](https://khan.github.io/KaTeX/docs/supported.html).
## Getting started
[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:
```html
```
#### In-browser rendering
Call `katex.render` with a TeX expression and a DOM element to render into:
```js
katex.render("c = \\pm\\sqrt{a^2 + b^2}", element);
```
If KaTeX can't parse the expression, it throws a `katex.ParseError` error.
#### Rendering expressions in text elements
To automatically render math in text elements, include the [auto-render script](https://khan.github.io/KaTeX/docs/autorender.html) `contrib/auto-render.min.js`, or via CDN:
```html
````
Then, call the `renderMathInElement` function with a DOM element containing expressions in a script tag before the closing body tag:
```html
...
```
See [Auto-render Extension](https://khan.github.io/KaTeX/docs/autorender.html) for more details.
#### 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`:
```js
var html = katex.renderToString("c = \\pm\\sqrt{a^2 + b^2}");
// '...'
```
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.
## Documentation
Learn more about using KaTeX [on the website](https://khan.github.io/KaTeX)!
## Contributing
See [CONTRIBUTING.md](CONTRIBUTING.md)
## License
KaTeX is licensed under the [MIT License](http://opensource.org/licenses/MIT).