Plag
Plag checks academic and other documents for plagiarism, translated matches, and AI-generated text. Students and educators use its scores, highlighted passages, and source links to review originality and citations.
Who it's for
- Students checking papers before submission for plagiarism, AI-generated passages, or translated matches.
- Educators who want to review student work and use a free account to check up to 20 documents per month.
- Writers working in multilingual contexts who need plagiarism checks across 100+ languages or AI detection across 50+ languages.
Not the right fit if…
- Educators who need to create student accounts themselves: the page says students must create their own accounts individually.
- Educators who need more than 20 checks per month at no cost: the stated free educator account limit is 20 documents per month.
How it fits your workflow
Upload a supported document or paste text. Plag checks it for plagiarism, AI-generated content, and translated plagiarism, then provides scores and highlights flagged passages.
Review matched sources and citation markings in the report, and use the results to revise the document. The page also offers expert services for citation help, plagiarism removal, and humanizing flagged text.
Pricing
Free: Free document checks are available. The page describes up to three free evaluations and says verified educator accounts can check up to 20 documents per month at no cost. Prices for paid services are not stated.
Free checks
Free
- · Initial plagiarism, AI, and translated-plagiarism evaluations are offered at no cost.
- · The free plagiarism check provides a similarity range; the page also describes a free full-document AI score.
- · Verified educator accounts can check up to 20 documents per month for free.
Prices checked on Nov 2, 2026 from the vendor's site. They can change; confirm before you buy.
Key features
- Plagiarism checking
- Compares document text with public and paid-access sources, including web sources and a scholarly-article database. The report highlights matches and links to their sources.
- AI text detection
- Provides an overall AI probability score and sentence-level indications of text flagged as AI-generated. The page states that detection supports more than 50 languages.
- Translated-plagiarism detection
- Checks for plagiarism across languages, including cases where content has been translated. Plagiarism checking is stated to support more than 100 languages.
- Citation and match highlighting
- Uses different colors to mark paraphrases, improper quotations, and proper quotations, helping users review citations and matched passages.
- Document reports
- Provides document scores and downloadable PDF reports; the plagiarism report includes links to matched sources.
- Expert editing services
- The page offers human services for citation help, plagiarism removal, and rewriting text flagged by the AI detector to sound more natural.
Limitations to know
- The free plagiarism check provides a similarity range rather than the exact similarity percentage, according to the FAQ.
- A free educator account is limited to checking 20 documents per month; students can share documents with the educator without that sharing counting against the limit.
- Educator account registration requires an institutional email and supporting proof of the educator's position.
- The page does not state prices for paid services.
Alternatives to consider
-
PlagiarismSearch.com
Choose it if you need API access or integrations, which its description lists alongside plagiarism and AI-generation detection.
-
Passed.AI
Choose it if your educator workflow specifically needs document audits, replay/history reports, or a Chrome extension.
-
Quetext
Choose it if you need features its description lists such as citation generation, bulk file scanning, or browser-extension access.
Getting started
- Upload a document in a listed format or paste its text.
- Review the available originality scores and report details.
- Educators registering for an educator account use an institutional email and upload proof of their position.
Frequently asked questions
How is the similarity check performed?
Plag says it extracts text from the uploaded file and compares it with public and paid-access document databases using text-matching algorithms. Similarities are highlighted, scores are calculated, and an originality report lists matches and sources.
What does the free check provide?
The FAQ says the free check provides a similarity range, a shareable similarity report, and a real-time plagiarism check. The page also describes free AI scores and up to three free evaluations.
Are uploaded documents added to comparison databases or shared with institutions?
Plag says uploaded documents are not included in comparative databases and are not shared with teachers, schools, or other third parties. It says access is limited to the user and authorized employees for customer-support purposes.
How many documents can an educator check for free?
The page says an educator account can check up to 20 documents per month for free, with no limit on the number of documents students can share with the educator.
How does an educator get an account?
The page says educators should register with an institutional email and upload a supporting document verifying their position, such as a director’s statement or work permit.