Simon Willison’s Weblog

GPT-3 token encoder and decoder. I built an Observable notebook with an interface to encode, decode and search through GPT-3 tokens, building on top of a notebook by EJ Fox and Ian Johnson.

Posted 27th April 2023 at 11:48 pm

Recent articles

Vibe engineering - 7th October 2025
OpenAI DevDay 2025 live blog - 6th October 2025
Embracing the parallel coding agent lifestyle - 5th October 2025

projects 498 ai 1604 observable 49 gpt-3 67 openai 357 llms 1382

Monthly briefing

Sponsor me for $10/month and get a curated email digest of the month's most important LLM developments.

Pay me to send you less!

Sponsor & subscribe