Text Diff — compare two texts free in your browser
Spot every change between two texts — added and removed lines, side by side.
This tool runs entirely in your browser. Your files are never uploaded — they stay on your device.
Need to see what changed between two versions of some text? Paste the original on the left and the updated version on the right, and this tool highlights exactly which lines were added and which were removed.
It runs entirely in your browser — your text is never uploaded or stored anywhere. That makes it safe for code snippets, contracts, configuration files and anything else you would rather keep off a stranger’s server.
How to use Text Diff
- Paste or type the original text into the left box.
- Paste or type the changed text into the right box.
- Click “Compare” to generate the line-by-line difference.
- Read the result: removed lines are red, added lines are green, unchanged lines stay neutral.
- Copy the result if you want to share or save the comparison.
Frequently asked questions
Is my text uploaded to a server?
No. The comparison runs entirely in your browser using JavaScript. Your text never leaves your device, so it is safe for private code, contracts and confidential notes.
How does the comparison work?
It compares the two texts line by line using a longest-common-subsequence algorithm — the same approach used by tools like diff and Git — to find the smallest set of additions and removals.
Can it compare individual words or characters?
This tool compares whole lines. If a line changes, it appears as one removed line and one added line. For prose, putting each sentence on its own line often gives the clearest result.
Is there a size limit?
There is no fixed limit, but because everything runs on your device, very large texts (tens of thousands of lines) may take a moment to compare.
Do I need an account or to install anything?
No. It works in any modern browser with no sign-up, no installation and no cost.