Remove Claude’s formatting from AO3
AO3 preserves pasted HTML, so copying straight from Claude carries its class names — the ones containing “claude” — into an Archive of Our Own work. They are invisible while you read, but present in the source and readable by anyone who looks. Edit the work, switch the editor to HTML mode, and delete any class attribute containing “claude”.
Check yours first. Paste the text into the free checker and it lists every artifact with its exact position — no account, nothing uploaded, unlimited.
Check my text →What AO3 keeps
- AO3's rich-text editor preserves a subset of pasted HTML, which is exactly how the class survives.
- This is the platform the “Claude AI detector” site skin was written for — it matches paragraphs whose class contains “claude” inside a work body.
- Pasting through a plain-text editor before AO3 prevents it entirely.
The fastest fix
Edit the work, switch the editor to HTML mode, and delete any class attribute containing “claude”.
That handles the markup. It does not handle zero-width characters, non-breaking and exotic spaces, smart quotes or em dashes — those are text rather than formatting, so they survive the paste route above and every other one.
How to check it worked
Post or preview the work, then use your browser's View Source and search for “claude”. AO3 shows you the posted HTML, so this is a definitive check rather than an inference.







