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

LLM predictions for 2026, shared with Oxide and Friends - 8th January 2026
Introducing gisthost.github.io - 1st January 2026
2025: The year in LLMs - 31st December 2025

css 231 fonts 12 javascript 732

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