How to use the Text Diff Checker
- Paste the original text on the left and the changed text on the right.
- Read the highlighted differences — changed words are marked within each line.
- Optionally ignore case or whitespace differences.
How the comparison works
The diff uses the Myers algorithm — the same approach as git diff — to find the smallest set of line insertions and deletions that turns one text into the other. For lines that changed, a second word-level diff highlights exactly which words differ.
Uses
- Comparing two versions of a contract, policy or essay
- Checking what changed between two configuration files or API responses
- Reviewing edits someone made to your text
Comparing files
To compare two files directly — including checking whether binary files are byte-for-byte identical — use File Compare.
Frequently asked questions
Why does a moved paragraph show as deleted and added?
Line diffs don't track moves; a paragraph that moved appears as a deletion in one place and an insertion in another.
Is there a size limit?
Texts of tens of thousands of lines work. Extremely different large texts are shown as a full replacement to keep the browser responsive.
Is what I enter stored or sent anywhere?
No. Calculations and processing happen in your browser. Nothing you type is sent to our servers. Some tools remember your last input in this browser's local storage for convenience; you can clear it at any time.