Added and removed lines
Lines present on only one side are labelled as additions or removals.
Compare text online.
Review two text versions side by side with line numbers and word-level highlights.
Runs locally in your browserFiles are not uploaded or storedNo sign-upPreparing required files for offline use…
How Diff Master compares text
Diff Master aligns two text versions line by line, then highlights changed words inside modified lines so you can separate edits from surrounding context.
- Paste the original text on the left and the changed text on the right.
- Select Compare Text to calculate additions, removals and modified lines locally.
- Use the result navigation to move through changes while keeping matching lines visible.
Modified lines
Related lines stay aligned and changed words receive an additional highlight.
Complete context
Unchanged lines remain available so the result can be read as a complete document.
Original
Ship the release on Monday.
Changed
Ship the release on Tuesday.
Expected result: The line is marked as modified, with “Monday” removed and “Tuesday” added.
Text comparison FAQs
Practical answers about how this tool compares content, what stays local and where its current limits are.
How do I compare two text versions?
Paste the original text on the left and the changed text on the right, then select Compare Text. The result keeps matching lines aligned and marks additions, removals and modified words.
Is the text sent to a server?
No. The comparison runs in your browser memory. Diff Master does not upload, store or log the text you paste into the comparison fields.
What differences does the tool show?
The result shows a complete side-by-side line view with line numbers. Removed content is red, added content is green, and modified lines include word-level highlights.
Can I compare long documents?
Yes, within the memory available to your browser. Very large inputs can take longer to calculate or render, so performance depends on the device and browser you are using.
Can I compare text copied from Word or a PDF?
Yes. Paste the extracted text into both panels. For PDF files, use PDF Compare when you also need page, layout, font or image differences.