Best AI Plagiarism Checkers in 2026
Updated
In short: Plagium is ranked #1 of 26 as of 4 October 2026, ahead of Check-Plagiarism and PrePostSEO Plagiarism Checker. The best-ranked option with a free plan is PlagAware. The lowest first paid tier on this page is PrePostSEO Plagiarism Checker at $0.35/mo.
AI plagiarism checkers can be compared by what they check, the documents they accept and how their results fit your review process. The ranking begins with Plagium and Check-Plagiarism, with PlagiarismCheck.org and PrePostSEO Plagiarism Checker among the next entries. Compared on AI writing checks and source coverage, the options also show maximum document word counts and supported file formats. LMS integrations and API access are useful points to weigh when considering system fit; report export, free-plan availability and paid-from pricing round out the comparison.
26 AI plagiarism checkers ranked on what their makers publish — plans and prices, free tiers, platforms and the facts on their own pages.
Recognised 40% · Phone app 26% · Documented 20% · Free plan 14% of the score
- 1 Plagium iPhone + Android RecognisedPhone appDocumentedFree plan 7.8Free Source coverage: web_only
- 2 Check-Plagiarism Android only RecognisedPhone appDocumentedFree plan 7.4$4.17/mo Source coverage: web_onlyMaximum document words: 7,000 wordsSupported file formats: doc, docx, txt, pdf
- 3 PrePostSEO Plagiarism Checker iPhone + Android RecognisedPhone appDocumentedFree plan 7.3$0.35/mo
- 4 PlagAware No phone app RecognisedPhone appDocumentedFree plan 6.4€2.99/mo
- 5 Noplag No phone app RecognisedPhone appDocumentedFree plan 6.3$9.99/mo
- 6 Proofademic No phone app RecognisedPhone appDocumentedFree plan 6.3$15/mo
- 7 SmallSEOTools Plagiarism Checker No phone app RecognisedPhone appDocumentedFree plan 6.3$7.84/mo
- 8 Plagiarisma No phone app RecognisedPhone appDocumentedFree plan 6.2Free Source coverage: web_academic_and_publisherSupported file formats: PDF, DOCX, RTF, TXT, HTML, PPTX, XLSX, XLS, FB2, ODT, EPUB, DOC
- 9 PlagiarismCheck.org No phone app RecognisedPhone appDocumentedFree plan 5.8
- 10 PlagiarismDetector.net No phone app RecognisedPhone appDocumentedFree plan 5.8$9.99/mo Source coverage: web_onlyMaximum document words: 25,000 wordsSupported file formats: TXT, DOCX, PDF, HTML
- 11 PlagiarismSearch No phone app RecognisedPhone appDocumentedFree plan 5.8$27.95/mo
- 12 Viper No phone app RecognisedPhone appDocumentedFree plan 5.8 Source coverage: web_academic_and_publisherSupported file formats: html, htm, txt, rtf, xml, md, pdf, docx, doc, pptx, ppt, odt, epub, odp, ppsx, pages, xlsx, xls
- 13 DupliChecker No phone app RecognisedPhone appDocumentedFree plan 5.7$9.99/mo
- 14 Turnitin Originality No phone app RecognisedPhone appDocumentedFree plan 5.7 Source coverage: web_academic_and_publisherSupported file formats: DOC, DOCX, PDF, PPTX, PPSX, XLS, XLSX, PS, RTF, HTM, HTML, WPD, ODT, TXT, HWP, HWPX
- 15 Turnitin Similarity No phone app RecognisedPhone appDocumentedFree plan 5.7 Source coverage: web_academic_and_publisherSupported file formats: DOC, DOCX, XLS, XLSX, PPT, PPTX, PostScript, PDF, HTML, HWP, RTF, ODT, WordPerfect, TXT
- 16 Plagius No phone app RecognisedPhone appDocumentedFree plan 5.6$0.41/mo Source coverage: web_onlySupported file formats: DOC, DOCX, PDF, OpenOffice, PPT, HTML, RTF, TXT
- 17 Copyleaks AI Detector No phone app RecognisedPhone appDocumentedFree plan 5.5
- 18 SearchEngineReports Plagiarism Checker No phone app RecognisedPhone appDocumentedFree plan 5.4 Source coverage: web_onlyMaximum document words: 5,000 wordsSupported file formats: DOC, DOCX, RTF, TXT, PDF, ODT
- 19 Plagiarism Checker X No phone app RecognisedPhone appDocumentedFree plan 5.2
- 20 Copyscape No phone app RecognisedPhone appDocumentedFree plan 5.1
- 21 PlagPointer No phone app RecognisedPhone appDocumentedFree plan 5.1 Source coverage: web_and_academicMaximum document words: 2,500 wordsSupported file formats: html, htm, txt, rtf, xml, md, pdf, docx, doc, pptx, ppt, odt, epub, odp, ppsx, pages, xlsx, xls
- 22 Scribbr Plagiarism Checker No phone app RecognisedPhone appDocumentedFree plan 5.1
- 23 Compilatio AI Detector No phone app RecognisedPhone appDocumentedFree plan 5.0
- 24 DrillBit No phone app RecognisedPhone appDocumentedFree plan 5.0
- 25 StrikePlagiarism No phone app RecognisedPhone appDocumentedFree plan 5.0
Is your app 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 AI plagiarism checker is ranked first on Samsung Mobile US Press?
Plagium is ranked #1 of 26 with a score of 7.8. Check-Plagiarism is second and PrePostSEO Plagiarism Checker third.
How many of these have a free plan?
6 of the 25 on this page publish a free plan on their own pricing pages.
Which is the cheapest paid option?
On this page, PrePostSEO Plagiarism Checker has the lowest first paid tier we found: $0.35/mo.
How is this list ranked?
Ranked mobile-first: a phone app alongside the web or desktop product, a free tier and the depth of its documentation. Paid placements never change a rank.