- Paste the original version into the left text area.
- Paste the edited version into the right text area.
- Read the highlighted result: additions, deletions and modifications are color-coded, with an optional side-by-side or unified view.
The comparison updates live as you type, and everything runs locally in your browser — nothing is uploaded, so you can diff drafts, contracts and code without privacy concerns.
The tool aligns the two texts line by line and marks the differences between them. Lines that appear only in the original are highlighted as removed, lines that appear only in the new version are highlighted as added, and lines that changed are shown side by side so you can see the old and new content at once. This makes it easy to review someone else edits, spot accidental deletions, and understand exactly what a revision changed before you accept it.
Tips
Diff the whole document first, then click into any changed block to see the detailed line-level change. When reviewing a long edit, focus on removed lines first — deletions are where content is most often lost accidentally. For code, diff against the previous version before committing so every change is intentional and reviewed.
Why use it
Spotting differences by reading two versions side by side is unreliable, and most desktop diff tools are built for developers. This checker gives everyone — writers, editors, students and developers — a clear, color-coded diff in seconds, with no signup, no upload and no cost. Paste two texts and see exactly what changed.
Real-world use cases
- Content production: Transform text for CMS, spreadsheets or translation workflows without manual retyping.
- Data handling: Clean and normalize strings before pasting into code, databases or AI prompts.
- Privacy-sensitive work: Process contracts, notes or personal text that you would never upload to a server.
How it compares
| Tool | Offline | Privacy | Install needed | Cost |
|---|---|---|---|---|
| This tool | Yes | 100% local | No | Free |
| Online server tools | No | Uploaded | No | Free/Ads |
| Desktop apps | Yes | Local | Yes | Paid |
When privacy and instant access matter, a browser-only tool is the most practical choice.
Pro tips
- For large texts, paste in chunks if your device is older. The tool still processes locally but will stay snappier.
- Combine with other tools: convert case, then run text analyzer for frequency, then encrypt if you need to share.
- Use diff mode to proofread translations or AI rewrites side-by-side before publishing.