Best Plagiarism Detection Software in 2026
Updated
In short: PlagiarismCheck.org is ranked #1 of 27 as of 3 October 2026, ahead of Noplag and PlagiarismDetector.net. The best-ranked option with a free plan is Noplag. The lowest first paid tier on this page is Plagius at $0.41/mo.
Reviewing writing for potential plagiarism calls for tools that fit both the material and the process around it. Compare maximum check size and supported languages against the documents you expect to review. AI detection and API access are also listed capabilities, while browser extensions and LMS integrations may matter for how checks fit into everyday workflows. Free-plan availability and paid-from pricing provide additional access considerations. PlagiarismCheck.org leads the ranking, followed by Noplag and PlagiarismDetector.net, with Originality.ai and Quetext AI Detector also among the first entries. Use these comparison points to assess what fits your review needs.
27 plagiarism detection software ranked on what their makers publish — plans and prices, free tiers, platforms and the facts on their own pages.
| # | Platform | Score | Why | From | Free plan | Paid from | AI detection | |
|---|---|---|---|---|---|---|---|---|
| 1 | PlagiarismCheck.org | 8.7 | RecognisedAPIDocumented | — | Yes | — | — | View |
| 2 | Noplag | 8.7 | RecognisedAPIDocumented | $9.99/mo | Yes | — | — | View |
| 3 |  PlagiarismDetector.net | 8.3 | RecognisedAPIDocumented | $9.99/mo | Yes | — | — | View |
| 4 | Originality.ai | 8.3 | RecognisedAPIDocumented | $12.95/mo | Yes | — | — | View |
| 5 | Quetext AI Detector | 7.8 | RecognisedAPIDocumented | $7.99/mo | Yes | — | — | View |
| 6 | Pangram | 7.7 | RecognisedAPIDocumented | $1.67/mo | Yes | — | — | View |
| 7 | Winston AI | 7.7 | RecognisedAPIDocumented | $0.42/mo | No | — | — | View |
| 8 | GPTZero | 7.7 | RecognisedAPIDocumented | $8.33/mo | Yes | — | — | View |
| 9 |  JPlag | 7.3 | RecognisedAPIDocumented | Free | Yes | — | No | View |
| 10 |  Noplag Engine | 7.1 | RecognisedAPIDocumented | $9.99/mo | Yes | — | No | View |
| 11 |  Plagium | 6.8 | RecognisedAPIDocumented | Free | Yes | — | — | View |
| 12 |  DupliChecker | 6.6 | RecognisedAPIDocumented | — | Yes | — | — | View |
| 13 | Scribbr Plagiarism Checker | 6.6 | RecognisedAPIDocumented | — | Yes | — | — | View |
| 14 |  SmallSEOTools Plagiarism Checker | 6.6 | RecognisedAPIDocumented | — | Yes | — | — | View |
| 15 |  Plagiarisma | 6.6 | RecognisedAPIDocumented | Free | Yes | — | — | View |
| 16 | Codequiry | 6.6 | RecognisedAPIDocumented | €25.76/mo | No | — | Yes | View |
| 17 | DrillBit | 6.4 | RecognisedAPIDocumented | — | No | — | — | View |
| 18 |  iThenticate | 6.3 | RecognisedAPIDocumented | — | No | — | — | View |
| 19 |  Plag.ai | 6.1 | RecognisedAPIDocumented | — | Yes | — | Yes | View |
| 20 |  Copyscape | 5.9 | RecognisedAPIDocumented | — | Yes | — | — | View |
| 21 |  PlagPointer | 5.5 | RecognisedAPIDocumented | — | No | — | — | View |
| 22 |  MOSS | 5.4 | RecognisedAPIDocumented | — | Yes | — | — | View |
| 23 | Copyleaks AI Detector | 5.3 | RecognisedAPIDocumented | — | — | — | — | View |
| 24 |  Dolos | 5.3 | RecognisedAPIDocumented | — | Yes | — | — | View |
| 25 |  Plagius | 5.0 | RecognisedAPIDocumented | $0.41/mo | No | — | — | View |
Is your platform on this list?
Numbered spots on this list can be sponsored. They are labelled, and the editorial order and scores never change for payment.
Questions about this list
Which plagiarism detection software is ranked first on Inferse?
PlagiarismCheck.org is ranked #1 of 27 with a score of 8.7. Noplag is second and PlagiarismDetector.net third.
How many of these have a free plan?
10 of the 25 on this page publish a free plan on their own pricing pages.
Which is the cheapest paid option?
On this page, Plagius has the lowest first paid tier we found: $0.41/mo.
How is this list ranked?
Ranked on what each maker publishes, open and connectable first: a public API, open-source code, the depth of its documentation and a free tier to try it on. Model lists are sorted by the figure in their title, exactly as each provider publishes it. Paid placements never change a rank.