Diff Checker
Compare two texts and see additions and removals line by line.
This diff checker online compares two blocks of text and shows exactly what was added, removed or changed between them. Paste the original on one side and the edited version on the other, then read the highlighted differences line by line. It is useful for comparing two versions of a contract, an essay, a config file, a JSON response or a piece of code when you need to find a small change in a large body of text. Developers use a diff checker for code and JSON, writers use it to review edits, and anyone can use it to confirm that a copied document matches the source. The tool is free, so you do not need a paid plan or an account, and it runs entirely in your browser. Your text is never uploaded to a server, which matters when you compare private or sensitive material. It also keeps working offline after the page has loaded.
Frequently asked
Is this diff checker online free?
Yes. It costs nothing, needs no sign-up, and has no limit tied to an account.
Can I use it as a diff checker for JSON or code?
Yes. Paste the two versions as plain text and the differences are highlighted, so it works for JSON, source code, configs and prose.
Is my text uploaded anywhere?
No. The comparison runs in your browser and your text stays on your device.
Can it compare PDF or Excel files?
This tool compares pasted text. For a PDF or spreadsheet, copy the text or cell values out and paste them into each side.
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