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

Embracing the parallel coding agent lifestyle - 5th October 2025
Designing agentic loops - 30th September 2025
Claude Sonnet 4.5 is probably the "best coding model in the world" (at least for now) - 29th September 2025

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