Simon Willison’s Weblog

Encoded Polyline Algorithm Format. Google Maps does some pretty crazy bit mangling to create compressed versions of lat/long pairs.

Posted 4th January 2008 at 4:12 pm

Recent articles

Large Language Models can run tools in your terminal with LLM 0.26 - 27th May 2025
Highlights from the Claude 4 system prompt - 25th May 2025
Live blog: Claude 4 launch at Code with Claude - 22nd May 2025

google-maps 53 latlong 1 polyline 1 encoding 5

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