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Prompt Diff Comparator

Prompt Diff Comparator

Compare prompt versions and map expected A/B outputs locally

Version A

Version B

A/B output matrix

InputExpected AExpected B

About this tool

Compare LLM prompt versions, placeholders, metrics, and expected A/B outputs locally. Prompt Diff Comparator runs in the browser on DevTools. There is no signup, and your input stays on this device unless the tool explicitly performs a live network lookup.

What this tool does not do

  • Prompt Diff Comparator is a free in-browser utility, not a hosted API. It does not keep server-side history and is not a substitute for production verification in your own stack.

How do I use this tool?

  1. How do I use Prompt Diff Comparator?

    Open Prompt Diff Comparator, enter or paste your input, and copy the result. The page works without an account.