Prompt diff
Compare two versions of a prompt word by word to see exactly what changed. Runs in your browser; nothing is uploaded.
See what changed between two prompts
When a prompt starts giving better or worse answers, the reason is often one changed sentence. Paste the earlier version in Before and the newer one in After to see the added and removed words.
Example
The example compares a vague request with a specific one. The diff shows the added limit ("at most five bullets") and the new ordering instruction, while {{team}} stays unchanged.
Check the newer version with the prompt checker, or estimate its size with the token counter.
Questions
How are the prompts compared?
Word by word. Spaces and {{variables}} count as their own pieces, so a changed word next to a variable does not mark the variable as changed too.
Can I compare long prompts?
Yes. Very long pairs are shown as fully removed and fully added text rather than word by word, so your browser stays responsive.
Is my text sent anywhere?
No. The comparison runs in your browser.
Can I keep versions automatically?
Yes. In your library every save keeps the previous version, so you can compare any version with the current one and restore it.
Keep your prompts
Save prompts you reuse in your own library: sections, {{variables}}, folders and version history. Creating an account is free, and saving or filling in prompts needs no AI provider.
More free tools
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- Prompt refiner
Paste a prompt and get a clearer, more specific version, with optional questions about what you need. Free to try without an account, within daily limits, where this site offers it.
- Prompt token counter
Estimate how many tokens a prompt uses and what it costs across current OpenAI, Anthropic and Gemini models. Runs in your browser; nothing is uploaded.