Dolos vs Noplag Engine
Dolos
dolos.ugent.beNoplag Engine
github.comSide by side
| Figure | Dolos | Noplag Engine |
|---|---|---|
| Price from | Free | $9.99/mo |
| Free plan | Yes | Yes |
| Free trial | — | Yes |
| Open source | Yes | — |
| Web | Yes | Yes |
| Windows | Yes | Yes |
| macOS | Yes | Yes |
| Linux | Yes | Yes |
| API | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 2 | 4 |
| Spec score · Plagiarism Detection Software | 9.0 (#5) | 8.5 (#11) |
| API | The JSON API accepts multipart ZIP uploads and returns report URLs and machine-readable report objects. | The engine exposes a `/v1` API with checks, reports, uploads, progress events, and corpus management, and ships without authentication. |
| Headquarters | Ghent, Belgium | San Francisco, United States |
| Integrations | Dolos provides a JSON API for automated integration with exercise platforms such as Dodona. | The Enterprise plan lists Canvas, Moodle, and Blackboard LMS integrations; the features page also names Brightspace via LTI 1.3. |
| Languages | Dolos uses Tree-sitter parsers and supports common languages including Bash, C, C++, C#, Elm, JavaScript, Java, PHP, Python, and TypeScript out of the box. | The hosted product says detection is calibrated for English, Spanish, Portuguese, Polish, and Ukrainian at launch. |
| Privacy | Team Dodona says it never shares submitted files or analysis reports and never uses them for commercial purposes; users can delete their data, and older data is periodically deleted. | The maker says submitted documents are never used to train models; hosted-plan retention is configurable and EU data residency is available on request. |
| Purpose | Dolos detects plagiarism by finding similarities between source code submissions. | Noplag Engine is an open-source plagiarism detection engine for verbatim and near-verbatim matching against a corpus you control. |
| Reports | Reports include similarity, total overlap, and the longest matching fragment for file pairs. | Reports include per-source similarity, matching passage offsets, and coverage accounting. |
Plans
Noplag Engine
- FreeFree
- Pro$9.99 a month
- Premium$19.99 a month
- EnterprisePriced on request
In their own words
Dolos
Dolos is a free, open-source tool for finding similarities between source-code submissions, particularly for teachers reviewing tests, exams, and exercises where collaboration may be allowed in small groups. Its analysis process tokenizes files, fingerprints token sequences, indexes matches, and produces reports. For each file pair, reports include similarity, total overlap, and the longest matching fragment. Dolos uses Tree-sitter parsers and supports languages including Bash, C, C++, C#, Elm, JavaScript, Java, PHP, Python, and TypeScript. The web app accepts ZIP files and detects languages from file extensions; in mixed-language archives, it analyzes only the dominant language unless a language is selected. Its public API accepts ZIP submissions up to 10 MB, with the CLI or library recommended for larger submissions. Analyses can also run locally, with results displayed in a browser, or on a self-hosted server. The free web app is hosted on Ghent University servers in Belgium. Dolos provides a JSON API for integrations such as Dodona and lists CSV as a report export format.
Noplag Engine
Noplag Engine is an open-source plagiarism detection tool that checks text for verbatim and near-verbatim matches against a corpus you control. It uses winnowing fingerprints to find candidate sources, then aligns matching character ranges. Reports show similarity by source, passage offsets, and coverage accounting. It accepts.txt,.md,.pdf, and.docx files, with folder ingestion and HTTP uploads, and exposes a /v1 API for checks, reports, uploads, progress events, and corpus management. The API ships without authentication. The open-source engine searches a local corpus; the hosted product also searches the live web. It does not detect paraphrase, semantic similarity, or AI-written text. The engine can run on your own hardware with Docker Compose under the Apache 2.0 license. The repository lists Python 3.12 or newer for development and PostgreSQL in its Docker Compose setup. The free hosted plan costs nothing and allows 3 checks per month, while self-hosting permits unlimited local checks. Pro costs $9.99 a month and Premium costs $19.99 a month; Enterprise pricing is custom.