Text Diff Checker

How to use it

1. 1Paste the original into the left box and the changed version into the right.
2. 2Read the counts — added, removed, unchanged — then scroll the comparison below them.
3. 3Turn on "ignore leading and trailing spaces" if indentation changes are cluttering the result.
4. 4Turn on "ignore case" when only capitalisation differs and you do not care about it.
5. 5If two lines look identical but show as different, an invisible character is usually the cause.

Frequently asked questions

Does it compare word by word or line by line?

Line by line. Changing one word marks the whole line as removed and re-added. That suits code and configuration; for prose, a word-level tool reads more naturally.

Is my text uploaded anywhere?

No. The comparison runs entirely in your browser, which is the point for contracts, config files with hostnames in them, or unreleased copy. Nothing is transmitted or stored.

How large a text can it handle?

Comfortably into the thousands of lines when the two mostly agree, because the identical head and tail are skipped first. Two entirely different large documents hit a safety cap and are shown as a wholesale replacement.

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• JSON Formatter and ValidatorPretty-print, minify or sort JSON, and get syntax errors reported by line and column with the offending line shown. Runs entirely offline.