Simon Willison’s Weblog

JavaScript/CSS Font Detector (via) Really clever trick: detects the fonts that you have installed by writing out some text and measuring its dimensions.

Posted 20th March 2007 at 11:20 pm

Recent articles

I think "agent" may finally have a widely enough agreed upon definition to be useful jargon now - 18th September 2025
My review of Claude's new Code Interpreter, released under a very confusing name - 9th September 2025
Recreating the Apollo AI adoption rate chart with GPT-5, Python and Pyodide - 9th September 2025

css 229 fonts 12 javascript 722

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