The short answer
A plagiarism percentage is the share of your text that matches other sources. Our plagiarism checker shows it for free, up to 1,000 words with no account, and links every match to its source. A free account includes 3,000 words a month. The number is a starting point. A score does not prove plagiarism, and a low score does not rule it out.
What the percentage measures
A checker splits your text, searches its sources, and counts what matches. So the number depends on three things:
- The matches it found. It can only find text in the sources it can search.
- What it counts. Tools differ on quotes, references and short common phrases.
- The length of your text. The same match is a bigger share of a short text.
It does not measure intent, and it cannot tell a cited quote from a copied sentence on its own. A person has to read each match.
A worked example
Here is the idea with simple numbers. Real tools count in their own ways.
| Part of a 1,000-word essay | Words | Is it a problem? |
|---|---|---|
| A quote in quotation marks, with a citation | 60 | No, if your course allows that much quotation |
| Common phrases, such as a course title | 20 | No |
| A sentence copied with no quotation marks or citation | 40 | Yes. Quote it and cite it, or rewrite it in your own words and cite it. |
| Total matched | 120, or 12% | Only the 40 words needed work |
So 12% here means 4% of the essay needed fixing. Another essay could show 5% with all of it copied without credit. For the difference, see how much plagiarism is allowed.
Why tools give different numbers
Run one paper through two checkers and you will likely get two percentages. They search different sources and count differently. Turnitin says it also compares work with a store of student papers, which other tools cannot search. So no independent tool can tell you in advance what Turnitin will show. If that is your concern, see Turnitin checker and Turnitin similarity score.
How to use the number
- Open every match. Read your sentence beside the source.
- Decide on each one. Add quotation marks, add a citation, or write the idea in your own words and cite it. See how to paraphrase.
- Find your rule. Your school, journal or client sets what is acceptable.
- Do not chase a number. The goal is that each source gets its credit.
To cite a source, try our citation generator. For longer documents, see our plans.