Free Wizard Migrates ChatGPT History to Claude Projects — Key Lessons on Token Limits and RAG

A developer built a free migration wizard that moves ChatGPT conversation history into Claude Projects, addressing the common pain point of years of context locked in ChatGPT. The tool is available at quitgpt-memory-kit.vercel.app and requires no code — it was built using Claude itself.

Key Technical Lessons

• Token limits are per-file, not per-size: A clean 26MB JSON file can still trigger "knowledge exceeds maximum" errors. The fix isn't compression or summarization — it's splitting the data by topic into 4-5 separate files, each fitting within the limit.
• Claude uses RAG for large Project files: It doesn't read the entire file at once. Therefore, queries must be specific: "What did we discuss about the Q2 launch strategy" works much better than "what did we talk about last month."

What the Wizard Does

The step-by-step wizard handles the export from ChatGPT and imports it into Claude Projects, automatically classifying and organizing conversations. The author is open to questions about the classification logic or handling large exports.

Who It's For

Developers using AI coding agents who have accumulated history in ChatGPT and want to leverage Claude's project memory without losing context.