ChatGPT to Claude

I've been using ChatGPT since it launched.

3+ years of conversations - ideas I was working through, decisions I was wrestling with, code I was debugging, things I was trying to learn. A pretty dense record of how I think.

When I switched to Claude as my primary assistant (thanks SDR for getting us to go this direction at Tandem), I felt the context disappear. Not just the conversations themselves, but the accumulated understanding of me that built up over time. Every new chat started from zero, the finely tuned system I had for writing and problem solving was absent. I did the usual coaching and rebuilding steps but when I finally decided to export my data from ChatGPT naively thinking “I'll just drop the .zip file in” I realized my 1GB+ history wasn’t manageable in 30MB chunks. OpenAI doesn’t create a portable data file, they provide a legally compliant data download. It’s a mess but I dont blame them, nobody wants to make data portability easy when paying customers are the business.

So I built something to fix that for myself.

ChatGPT to Claude is a small macOS app. You drop in your ChatGPT export ZIP, it processes everything, and writes your conversation history to a folder Claude can actually use - either through Claude Desktop's Projects feature, or through an MCP server that lets you say "load my ChatGPT history" and have it available in any new chat.

All without needing to setup the Claude API or do any technical wizardry to bypass the 30MB upload limit in the UI.

The export is organized to be readable, usable, and importable, not just archived:

Conversations sorted by year, as markdown
All images and files extracted to a media/ folder
Group chats preserved separately
A START_HERE.md that Claude reads automatically and uses to understand your history and get everything pulled in as conversations and projects.

That last part was important to me. I didn't want to just dump raw JSON files that happen to be accessible. I wanted Claude to actually know what it was looking at (with some guidance from you).

If you're moving from ChatGPT to Claude (or just augmenting your workflow with both!) and want to bring your history with you easily, download ChatGPT to Claude here.

(There’s a reason I always say “Made For Me” on these little experiments . . . because that’s what they are. It may not be how you would have done it, and you may not like it. That’s okay, grab the source code and make it for you. Share it my way when you do and let me be your cheerleader.)

THOUGHTS