JPlag

6.9easy start · #12 of 28
in Plagiarism Detection Software

Free to practise onyes
Free trialnot on record
Well documentedyes
Runs where you workyes

Runs on api, Linux, Mac, self-hosted, Windows.

JPlag is ranked #12 of 28 in plagiarism detection software on The Geeks Club. It runs on API, Linux, macOS, Self-hosted, Windows. There is a free plan.

JPlag plans and pricing

All plans

JPlag Free Open-source software · runs locally · requires Java SE 25 github.com · 29 Sept 2026

Compared on plagiarism detection software

Free plan: Yes
AI detection: No
LMS integrations: No
API access: Yes
Browser extension: No

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The record

Purpose: JPlag finds pairwise similarities among programs to detect source-code plagiarism and collusion.
How it compares: It analyzes programming-language syntax and program structure, which helps it detect similarities despite some obfuscation attempts.
Local processing: The project says analysis runs on the user's machine and sends no data externally.
No internet search: JPlag compares submissions with one another and does not compare them against the internet.
Languages: The README lists support for Java, C, C++, C#, Python, JavaScript, TypeScript, Go, Kotlin, R, Rust, Swift, Scala, LLVM IR, Scheme, EMF, SCXML, text, and multi-language submissions, with varying maturity levels.
Interfaces: JPlag can be used through its command-line interface or Java API, and the CLI can launch the report viewer.
Integration: JPlag is published on Maven Central for inclusion as a dependency in Java projects.
Report limit: The report's top list and code comparison include at most 2,500 pairs by default; this limit can be changed with the -n option.
Sensitivity: Lowering the minimum matching-token length increases sensitivity but may also increase false positives.
Use cases: The project describes use in programming education and says it can also identify duplicated or slightly modified software parts.
Runtime requirement: The README says Java SE 25 is required to run or build JPlag.
Support: The project directs users to report bugs and issues on GitHub and provides a Q&A discussion section.
Project history: JPlag was originally developed at Karlsruhe Institute of Technology in 1996 and is maintained primarily by KIT researchers.
Founded: 1996
Price from: Free

Where it ranks on The Geeks Club

Best Plagiarism Detection Software in 2026#12 of 28

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Sources

github.com/jplag/JPlag/wiki· checked 29 Sept 2026
github.com/jplag/JPlag/blob/main/README.md· checked 29 Sept 2026
github.com/jplag/JPlag· checked 28 Sept 2026