Simon Willison’s Weblog

Visual Security: 9-block IP Identification. Smart (and pretty) trick for showing a representation tied to a commenter’s IP address without affecting their privacy.

Posted 18th January 2007 at 4:55 pm

Recent articles

ChatGPT agent's user-agent - 4th August 2025
The ChatGPT sharing dialog demonstrates how difficult it is to design privacy preferences - 3rd August 2025
Reverse engineering some updates to Claude - 31st July 2025

9block 1 donpark 1 ip 4 privacy 55

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