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Best Plagiarism Checkers in 2026
When you need to check a document for matching material, start by comparing what sources each checker covers and how much text it accepts. Academic source matching and web source matching are separate measures; supported languages and word limits help clarify the scope. Noplag, Originality.ai, and PlagAware are among the named options. For a writing or teaching workflow, check LMS integration, API access, and report export formats. Free-plan availability and paid-from pricing provide additional access details, so weigh them alongside the matching coverage and reporting options relevant to your work.
- 31 apps
- Research read 23 Sept 2026
- How the order is worked out
- 1
Dolos
Free plan Open source APILinuxMac+3Dolos focuses on similarities between source code submissions, with reports that show overlap at the file-pair level.
- 2
Noplag
Free plan Open source APILinuxMac+3Noplag provides source-linked matching reports for verbatim and near-verbatim copying, with multiple submission formats and a free tier.
- 3
Copyleaks AI Detector
Free plan APIExtensionSelf-hosted+1Copyleaks combines multilingual AI-text detection with explanations, integrations, and an API.
7.7 Visit site - 4
Copyscape
Free plan APISelf-hostedWebCopyscape offers URL checks as well as paid options for document checks, batch searches, and monitoring. Treat AI detector results as one input rather than a sole basis for disciplinary decisions.
- 5
JPlag
Free plan APILinuxSelf-hostedChoose JPlag if you need local pairwise analysis of program submissions, especially for student exercises or duplicated code.
- 6
Originality.ai
Free plan APIExtensionWebOriginality.ai combines AI detection with plagiarism, fact, readability, and writing checks across web, extension, and API options.
- 7
Plagiarisma
Free plan AndroidAPIExtension+2Plagiarisma combines text originality checks with tools for paraphrasing and AI detection across its web, Windows, and Docs offerings.
- 8
DupliChecker
Free plan APIWebChoose DupliChecker if you want online plagiarism checking alongside SEO tools, or a free AI detector that accepts pasted text and file uploads.
- 9
MOSS
Free plan LinuxWebMOSS can surface similar passages across programming submissions, but it does not determine whether plagiarism occurred.
- 10
PlagAware
Free plan APIWebPlagAware combines text matching, web monitoring and an AI detector, with reports and multiple submission options. Its exclusion of non-public paid sources is an important coverage limit to consider.
- 11
PlagiarismCheck.org
Free plan APIExtensionWebChoose PlagiarismCheck.org if you need originality, authorship or AI-content checks with browser access and PDF reports.
- 12
PlagiarismSearch
Free plan APIExtensionWebChoose PlagiarismSearch if you need similarity reports, AI-writing indicators or integrations such as Moodle and Google Docs.
- 13
PrePostSEO Plagiarism Checker
Free plan AndroidAPIiPhone+3PrePostSEO offers several ways to submit text and review matched sources, with downloadable reports and linked writing tools. Free use is limited, and the paid plans have differing submission limits.
- 14
Smodin Plagiarism Checker
Free plan AndroidAPIExtension+2Smodin provides source matches and highlighted text to help users review possible overlap.
- 15
Plag
Free plan WebPlag combines plagiarism and AI checks with similarity reports that link to matching sources.
- 16
Plagiarism Checker X
Free plan WindowsPlagiarism Checker X combines online similarity checks with bulk document comparison, readability analysis, and report exports.
- 17
Plagiarism Detector
Free plan WebWindowsPlagiarism Detector combines document matching, AI-content detection, and report exports, with both web and local-network search options.
- 18
Quetext AI Detector
Free plan APIExtensionWebQuetext combines AI detection with plagiarism checks and offers browser, API, and report workflows.
- 19
SmallSEOTools Plagiarism Checker
Free plan APIExtensionWebSmallSEOTools Plagiarism Checker offers multiple input methods, match details, and report exports, with a free scan cap of 1,000 words.
- 20
Plagramme
Free plan WebPlagramme combines website, academic-source, and AI-text checks in one web service. A free plan is available, while paid tiers add larger credit allowances and support.
- 21
Scribbr Plagiarism Checker
Free plan WebScribbr offers a free initial report and detailed paid reports for academic checks, with support for multiple languages and file formats.
- 22
Viper
Free plan WebViper offers document checks, configurable scan controls, and downloadable reports through a web app.
- 23
DrillBit
Paid AndroidAPIiPhone+1DrillBit combines source matching with AI-content detection and several integration routes, serving both individual and organizational use.
- 24
Plagius
Free trial MacWebWindowsPlagius combines document similarity checks with an AI-generation estimate and detailed reports.
- 25
Crossref Similarity Check
Paid APIWebSimilarity Check offers manuscript comparison and editorial reports for qualifying Crossref members.
#1Places #1, #2, #3, #4, #5 on this list can be bought by the makers of the software on it. See the price
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