Text Diff Checker
Compare two texts and see exactly what changed — side by side or unified, with word-level highlighting.
Differences
100% private: everything runs in your browser and nothing is uploaded.
How to Compare Two Texts
No sign-up, no installation — it works right here in your browser.
- Step 1:Paste the original text on the left and the changed text on the right, or click Load sample.
- Step 2:Choose side-by-side or unified view and, if needed, ignore case or whitespace or hide unchanged lines.
- Step 3:Review the highlighted differences: red lines were removed, green lines were added and changed words are marked inside each line.
Text Diff Checker FAQ
How does the diff checker find differences?
It uses the Myers diff algorithm — the same approach used by Git — to calculate the smallest set of line insertions and deletions that turns the original text into the changed one, then compares modified lines word by word.
What is the difference between side-by-side and unified view?
Side-by-side shows the original and the changed text in two aligned columns, which is easiest to read. Unified view lists removed lines with a minus sign and added lines with a plus sign in a single column, like the output of git diff.
Can I ignore whitespace or letter case?
Yes. Ignore whitespace treats lines as equal when they differ only in spaces, tabs or indentation, and Ignore case treats uppercase and lowercase letters as the same.
Can I compare code files?
Yes. Paste any source code, JSON, YAML, SQL, CSV or plain text. The comparison works line by line, so it suits code reviews, configuration changes and log comparisons.
Is my text uploaded to a server?
No. The comparison runs entirely in your browser, so confidential documents and proprietary code never leave your device.
Compare Text and Code Online
Spotting what changed between two versions of a document by eye is slow and unreliable. A diff checker compares the texts line by line and shows exactly which lines were added, removed or modified. This free online diff tool uses the same Myers algorithm as Git to find the smallest set of changes, then highlights the individual words that differ inside each modified line, so even a single changed character in a long configuration value stands out immediately.
Use it to review code before a commit, compare configuration files between environments, check what an editor changed in a contract or article, or verify the output of a script against an expected result. Switch between a side-by-side view and a compact unified view, ignore differences in letter case or whitespace, and collapse unchanged lines to focus on what matters. Comparisons of up to 20,000 lines per text run entirely in your browser, so confidential code and documents are never uploaded.