Text Diff Checker
Paste an original and a changed version of a text to instantly see exactly which lines were added or removed.
Your files are processed locally in your browser. They are not uploaded to our servers.
How to use
- Paste the original text into the first box.
- Paste the changed text into the second box.
- Review the line-by-line comparison below, with additions and removals highlighted.
What is this tool?
Text Diff Checker compares two blocks of text line by line and highlights exactly what changed — added lines in green, removed lines in red — using the same longest-common-subsequence approach used by version control tools. Everything is computed instantly in your browser.
Common uses
- Reviewing changes between two drafts of a document
- Comparing two versions of code, config or data
- Spotting exactly what changed in an email or contract revision
- Checking the difference between two lists or exports
Related tools
FAQ
Does this compare word by word or line by line?
The comparison works line by line, which is the clearest way to see structural changes in most text.
Is there a limit on how much text I can compare?
There's no hard limit, but very large texts may take a moment longer since the comparison runs in your browser.
Is my text uploaded anywhere?
No, both texts are compared entirely locally in your browser and never leave your device.