Free Text Compare & Diff Checker
Compare two blocks of text and see every added, removed and unchanged line or word. Runs in your browser - nothing is uploaded.
Similarity is twice the number of matched units divided by the total units in both texts, so two identical texts read 100% and two texts sharing nothing read 0%.
Turn output into a monitored workflow
A Novaverb workspace crawls your live site, verifies these tags and files are actually served, tracks changes over time, and turns findings into assigned work.
Text Compare
Compare two versions of the same text
Paste the earlier version on the left and the newer one on the right. The comparison runs as you type: every unit is marked unchanged, added or removed, and the counters show how much actually moved rather than how much looks different.
Line mode or word mode
Line mode is the right choice for code, configuration files, robots.txt, CSV rows and anything where a line is a meaningful unit. Word mode is better for prose, where a single edited word would otherwise mark a whole paragraph as changed.
Why a moved block is not reported as a rewrite
The comparison finds the longest common sequence between the two texts instead of comparing position by position. A paragraph moved further down is reported as one removal and one addition, not as every line in between having changed.
Where this helps an SEO or content workflow
- Check exactly what an editor, a plugin or a migration changed in a page before it goes live.
- Diff a robots.txt, a sitemap or a redirect map against the version you are about to deploy.
- Confirm that a rewritten page kept the headings, entities and claims you intended to keep.
- Compare a draft against the published version when you do not have version control on the content.
Text Compare FAQ
Is my text sent anywhere?
No. The comparison runs entirely in your browser, so a contract, an unpublished draft or a configuration file never leaves your machine. There is no request to compare, which is also why there is no server-side limit on this tool.
What does the similarity percentage mean?
It is twice the number of matched units divided by the total number of units in both texts. Two identical texts read 100%; two texts with nothing in common read 0%. It is a description of this comparison, not a plagiarism score or an originality verdict.
Why is there a limit on how much text I can compare?
The matcher compares every unit in one text against every unit in the other, so the work grows with the product of the two lengths. The cap keeps a very large paste from freezing your own browser tab. When it applies, the tool says so and tells you how much it compared.
What is the difference between line mode and word mode?
Line mode treats each line as one unit, which suits code and configuration. Word mode treats each whitespace-separated word as one unit, which suits prose - changing one word marks one word instead of the whole paragraph.
What do the plus and minus markers in the downloaded file mean?
In line mode the file follows the familiar diff convention: a leading minus is a line only in the original, a leading plus is a line only in the changed text, and a leading space is a line present in both. Word mode uses the wdiff convention instead, marking removals and additions inline.
Can it tell me why something changed?
No. It reports what differs between the two texts you pasted. It has no knowledge of who edited them, when, or for what reason - a diff is evidence of a change, not an explanation of one.
Is my data uploaded anywhere?
No. This generator runs fully client-side in your browser. Nothing you type is sent to a server, so it is safe to use on private content.
Is it really free?
Yes, with no account. A Novaverb workspace is only needed when you want to verify, monitor, and track these files on your live site over time.