Simon Willison releases online LaTeX renderer

The tool renders LaTeX source placed in the URL's #fragment directly: single formulas are typeset with MathJax, while full documents or prose fragments use faster-latex. A live preview sits beside the editor, and a toolbar toggles between edit and render views. Source can be typed manually, loaded from a URL or GitHub Gist, or picked from built-in examples; since LaTeX stays in the URL fragment, it can be shared as a readable or compressed link. It uses Pako 2.1.0, MathJax 4.1.3, faster-latex 0.3.1, and DOMPurify 3.4.16, borrowing the iframe sandbox mechanism from the author's earlier SVG in Markdown tool to guard against XSS, and reusing the load-from-URL-or-Gist feature. For developers who often paste math into web pages, write course materials, or organize paper fragments, this means no local TeX distribution is needed—just drop the source into a link and the recipient sees the typeset result. However, rendering happens entirely client-side, so layout quality for complex documents and load size remain limited by the chosen libraries.