Text Diff — Free Online Text Comparison Tool
Paste two versions of a text and see exactly what changed. All processing happens in your browser.
What Is a Text Diff Tool?
A text diff tool compares two versions of a text and highlights exactly what changed — which lines were added, removed or left untouched. "Diff" comes from the classic Unix diff command that programmers have used for decades to review code changes.
This online version works the same way without any setup: paste the original on the left, the new version on the right, and get a color-coded result instantly. Removed lines show in red, added lines in green, unchanged lines stay neutral.
How to Use This Text Diff Checker
Step 1 — Paste the original text into the left box.
Step 2 — Paste the modified text into the right box.
Step 3 — Click "Compare texts". The highlighted diff appears below, with a summary of how many lines were added and removed.
Use Swap to reverse the two sides, or Clear to start over.
When to Use Text Diff
Comparing Document Versions
See exactly what changed between two drafts of a contract, article or report — no more reading both versions side by side line by line.
Checking Code Changes
Paste two code snippets to review what was modified before committing or deploying. The line-by-line view makes small but critical changes obvious.
Proofreading Edits
Compare your draft before and after an editor's pass to see every edit. Great for learning from corrections and for approving changes.
Detecting Plagiarism
Compare a submitted text against a suspected source. Large unchanged blocks stand out immediately in the diff view.
FAQ
How do I compare two texts online?
Paste the original text into the left box and the modified version into the right box, then click Compare. Added lines are highlighted green and removed lines red.
How do I compare two Word documents?
Copy the text from each Word document and paste the two versions into this tool. For a built-in option, Word's Review tab also has a Compare feature.
Can I compare code with this tool?
Yes. Paste two code snippets and the tool compares them line by line, highlighting added and removed lines — handy for reviewing small changes.
Does this tool store my text?
No. The comparison runs entirely in your browser with JavaScript. Your text is never uploaded or stored anywhere.
Is this text diff tool free?
Yes — free forever, with no sign-up required.