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

Your job is to deliver code you have proven to work - 18th December 2025
Gemini 3 Flash - 17th December 2025
I ported JustHTML from Python to JavaScript with Codex CLI and GPT-5.2 in 4.5 hours - 15th December 2025

css 230 fonts 12 javascript 728

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