This tool compares two texts you paste. It does not search the web.
How to use the text similarity checker
What this tool is (and is not)
It is a comparison tool: you supply both texts, it measures how much they overlap. It is not a plagiarism checker — it compares two texts you paste and does not search the web, so it cannot find copies of your work elsewhere.
How the score is built
Two measures are averaged. Word overlap compares the vocabularies of both texts (shared distinct words ÷ all distinct words). Line overlap does the same with whole lines. Any line that appears word-for-word in both texts is listed under the score, so you can see exactly what is shared.
Good uses
Compare a rewrite with the original before publishing. Check that two product descriptions or captions are not accidentally near-identical. Verify a paraphrase genuinely rewords the source.
Example
Two captions that differ by only a couple of words score in the high 80s and list their shared line underneath. Two texts about completely different topics, sharing no words, score 0%.
Frequently asked questions
Is this a plagiarism checker?
No, and we will not call it one. This tool compares two texts that you paste in. It does not search the web, any database, or anyone else's work, so it cannot tell you whether a text appears somewhere online.
How is the similarity percentage worked out?
We average two measures: word overlap (the Jaccard index of the two vocabularies — shared words divided by all distinct words) and line overlap (the same measure applied to whole lines). Identical texts score 100%; texts sharing no words score 0%.
What is it useful for, then?
Checking a rewrite against its original, spotting near-duplicate product descriptions or social posts, comparing two drafts of the same caption, and confirming that a paraphrase actually changed the wording.
Does word order matter?
For the word-overlap measure, no — it compares vocabularies, not sequences. The identical-lines list is where order and exact wording show up.
Are the texts I paste uploaded?
No. The comparison runs in your browser only.
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