# A contender for MathJax?

Khan Academy released KaTeX, a library that does essentially the same job as MathJax does today -- only faster. Part of that is probably because (the hard?) part of the layout can be preprocessed on the server. This may also enable mathematics typesetting in apps more easily.

As of now, it does not offer all the symbols and functions MathJax has -- so we don't want to switch now -- but eventually we should consider moving over. MathJax is nice but it is just painfully slow on pages with many formulae, which sites like (math|cs|cstheory).SE have plenty.

Using KaTeX as primary engine with MathJax as fallback will soon be available; this solution would already speed up many a page.

Some site metas have picked this up:

• Well, try \sum\nolimits and it won't produce output; the output of \det_X is painfully wrong. – egreg Sep 16 '14 at 9:30
• What exactly is the question here? Considering that KaTeX is not currently on par with MathJax, requesting SE to switch engines would be premature – except that you're not asking such a thing at all. So is this post merely meant to raise awareness? – amon Sep 16 '14 at 13:25
• @amon Yes. Depending on the speed of development, KaTeX may be a viable alternative sooner rather than later (especially if a MathJax fallback exists). Best SE starts looking at it now. – Raphael Sep 16 '14 at 15:50
• – Raphael Sep 21 '14 at 18:44
• I tried KaTeX and it looks to be extremely limited at the moment. Even common and standard LaTeX such as \mathbf or \sim doesn't work. With these limitations it's simply unsuitable for sites such as Math.SE, Stats.SE or Mathematica.SE ... – Szabolcs Nov 6 '14 at 21:52
• I despise MathJax's reflow and slow rendering, and would love to see this change. What about phasing it in as an option users can set in their profile (with a warning that some content might not display right)? Having users who want KaTeX be able to use it on SE sites would help them find remaining deficiencies and report or patch them upstream. – R.. Oct 10 at 15:13