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

The last six months in LLMs, illustrated by pelicans on bicycles - 6th June 2025
Tips on prompting ChatGPT for UK technology secretary Peter Kyle - 3rd June 2025
How often do LLMs snitch? Recreating Theo's SnitchBench with LLM - 31st May 2025

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