Compare API responses — what changed between the two?

Regression debugging usually starts with "the response is different now". Paste the old and new response — get a field-level diff with sizes and token counts. Fully local.

How to use response comparison in API debugging

1. Capture both — the last-known-good response and the current one (browser DevTools → copy response).
2. Diff them here first — 90% of regressions are a renamed field, a dropped key, or a type change (string vs number) visible instantly in the changed list.
3. Check the counts — an added field in a response can break strict client parsers; a removed one breaks them outright.
4. Paste the diff, not the payloads — when asking an AI for help, this summary saves hundreds of tokens.

Is my data uploaded anywhere?

No. This page is a single static HTML file — comparison runs entirely in your browser. Disconnect from the internet after it loads.

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