Treetok shows the token count for Claude and OpenAI in a directory structure. I built it because this one folder I was working in filled up the context window quick, and wanted to know why. I could have used line count instead, but I wanted more precision.

Through it, I learned that the same files in Claude cost 20-30% more tokens than OpenAI. So the same 200k context window in Claude is similar to 150k in Codex.