Prompt Diff Checker
NewCompare two versions of an LLM prompt side by side with word-level highlighting and an approximate token-count change.
prompt diffprompt comparisonprompt versioningtext diff for prompts
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Frequently Asked Questions
Why diff prompts?
Small wording changes can shift model behavior. A word-level diff shows exactly what changed between prompt versions.
How is the diff computed?
With a longest-common-subsequence comparison on words and whitespace, shown as green additions and red strikethrough removals.
Is the token change exact?
It is an estimate (about 4 characters per token), good for spotting growth but not billing.
Is my prompt uploaded?
No, the comparison runs locally in your browser.
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