Text Diff — Compare & Spot Changes
Paste two versions of any text and instantly see every addition, deletion, and modification — line by line.
Original Text
Modified Text
Use Cases
Built for writers, developers, and editors who need to track changes fast — no version control needed.
Compare code snippets between commits to review exactly what changed — line by line, without needing git diff.
See what your editor changed between draft versions of articles, essays, proposals, or legal contracts.
Compare student submissions side-by-side to quickly spot similarities, paraphrasing, and copied content.
How It Works
Simple diff comparison in three steps — no login required.
Paste Both Versions
Paste the original text on the left and the modified version on the right. Both fields support unlimited length.
Click Compare
Our diff engine runs a line-by-line comparison, calculating similarity percentage and categorizing every change.
Review Changes
Scroll through every addition, deletion, and modification. Each line is color-coded with a +/- indicator.
Frequently Asked Questions
How is similarity calculated?
We use the Ratcliff-Obershelp algorithm (Python's difflib.SequenceMatcher) which measures the ratio of matching to non-matching line sequences. 100% means identical texts, 0% means completely different.
Is there a text size limit?
No strict limit, but very large texts (100,000+ lines) may take longer to process. For optimal performance, we recommend comparing texts under 10,000 lines each.
Is my data private?
Yes. Text diff comparison is free and requires no login. Your text is processed server-side and never stored, logged, or shared with third parties.