DarnlyDiff checker: compare two texts
Paste two versions of anything, and see exactly what was added, removed and changed, down to the word.
See the patch (unified diff)
Comparing API responses? Turn them into types with the JSON to TypeScript tool.
More free tools
How it works
- Paste the old version in Before and the new one in After. You can also drop a file onto either box.
- The comparison at the top updates as you type. Removed lines are red, added lines are green, and the exact words that changed are highlighted inside each line.
- Turn on Ignore spaces or Ignore case to hide changes that don’t matter, or JSON to format both sides first. Then copy the result as a patch, or as a prompt for your AI agent.
Questions
How do I compare two texts?
Paste one version in Before and the other in After. The differences show right away at the top: red for removed, green for added, with the changed words highlighted.
Can I see what my AI agent changed in a file?
Yes. Paste the file from before the change and the file after it. Then click “Copy prompt for your AI agent” to ask it to explain the change and check for mistakes.
What does “Ignore spaces” do?
It treats lines as the same when only spaces, tabs or indentation differ. Useful when code was reformatted.
How does JSON mode work?
Both sides are formatted the same way and their keys are sorted before comparing. So only real changes in values show up, not changes in order or spacing. If a side isn’t valid JSON, it’s compared as plain text and you’ll see a note.
What is a patch?
A patch is the standard way to write down a diff (the same format as git diff). Lines starting with - were removed and + were added. You can apply it with git apply or patch.
Is my text uploaded?
No. The comparison runs in your browser, so nothing you paste leaves your computer.