MOSS vs Noplag
MOSS
theory.stanford.edu
Noplag
noplag.comSide by side
| Figure | MOSS | Noplag |
|---|---|---|
| Price from | Free | $9.99/mo |
| Free plan | Yes | Yes |
| Free trial | — | Yes |
| Open source | — | Yes |
| Web | Yes | Yes |
| Windows | — | Yes |
| macOS | — | Yes |
| Linux | Yes | Yes |
| API | — | Yes |
| Self-hosted | — | Yes |
| Plans published | 1 | 4 |
| Spec score · Plagiarism Checkers | 7.7 (#18) | 9.2 (#3) |
| Spec score · Plagiarism Detection Software | 7.7 (#20) | 9.1 (#4) |
| Founded | 1994 | 2014 |
| Languages | It analyzes C, C++, Java, C#, Python, Visual Basic, JavaScript, FORTRAN, ML, Haskell, Lisp, Scheme, Pascal, Modula2, Ada, Perl, TCL, Matlab, VHDL, Verilog, Spice, MIPS assembly, a8086 assembly, and HCL2. | Detection is calibrated at launch for English, Spanish, Portuguese, Polish, and Ukrainian. |
| Retention | Results are typically deleted after 14 days and may be deleted earlier when server disk space is constrained. | Document content is purged 30 days after a free-tier check; paid users can choose a 30-, 60-, or 90-day retention window, while Enterprise can retain it without limit. |
Plans
In their own words
Noplag
Noplag is an open-source plagiarism checker with a hosted cloud service and an engine released under Apache 2.0. Its current matching uses winnowing fingerprints and live-web comparison to find verbatim and near-verbatim copying; it does not detect paraphrase. Sources include the open web, Common Crawl, Wikipedia, academic indexes, the Noplag Database and users’ own folders. Submit DOCX, PDF, TXT, ODT or RTF files, paste text or provide a URL. Reports link matches to their sources, display similarity scores and exact overlapping text, and can be exported as PDFs. Detection is calibrated at launch for English, Spanish, Portuguese, Polish and Ukrainian. AI-content detection is marked as coming soon and intended as a separate signal. The free plan allows three checks per month, up to 2,500 words per check, with community Discord support. Pro costs $9.99 a month and includes 50 monthly checks, up to 25,000 words per check, database and academic-index matching, REST API and webhooks, and email support. A 14-day trial is listed.