Simon Willison’s Weblog

Cartographer.js. “Thematic mapping for Google Maps”—which means an easy way of adding heat maps (aka chloropleths), pie charts and point clusters as a layer over a Google map.

Posted 1st November 2009 at 1:20 pm

Recent articles

How Rob Pike got spammed with an AI slop "act of kindness" - 26th December 2025
A new way to extract detailed transcripts from Claude Code - 25th December 2025
Cooking with Claude - 23rd December 2025

catography 1 chloropleths 1 google 392 google-maps 53 graphs 7 heatmaps 3 infographics 7 mapping 54 maps 43 piecharts 1 visualisation 15

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