Best Plagiarism Checker Software

PlagScan was a German built plagiarism checker, later acquired by Turnitin, that detected overlapping text of three or more consecutive words using Microsoft Bing search results plus a database of academic and scientific journals. Reports highlighted exact matches in red and rewritten phrases in blue, and the platform let users exclude specific URLs, sources, or phrases from a scan. It supported document upload, copy and paste, and URL submission, along with an API for automated LMS integration.

As of the end of 2024, PlagScan stopped selling private individual plans, and remaining credits had to be used by December 31, 2024. Historical private pricing ranged from $5.99 for entry level plans up to around $22.99 per month for Enterprise, with higher Platinum tiers reaching several hundred dollars. Organizations are now directed to Turnitin's other academic integrity products.

PapersOwl's plagiarism checker is a free tool offered by the PapersOwl essay writing platform, aimed mainly at students who need a quick originality check before submitting academic work. It uses AI powered deep search algorithms to scan submitted text against a large volume of online material and returns a report highlighting matched passages along with their original sources. The checker has no stated word limit and is available at any time without a paid account.

The first two checks can be run without registering, after which users are asked to sign up with an email address to continue using the tool for free. The plagiarism checker itself carries no charge; PapersOwl's revenue instead comes from separate paid essay writing, editing, and rewriting services offered elsewhere on the site.

Chegg Writing is a subscription writing tool from Chegg that combines a grammar checker, a plagiarism checker, and a citation generator in one product. The plagiarism checker compares submitted text against billions of web pages, highlights matching passages, and links back to the original source so students can properly cite or revise flagged sections. The citation generator produces free automatic citations in more than 7,000 styles, including APA, MLA, and Chicago.

Chegg Writing costs $9.95 per month after a 3-day free trial, billed automatically unless cancelled. It can also be accessed through the $19.95 per month Chegg Study Pack, which bundles Writing with Chegg Study and Math Solver. The tool also offers an optional Expert Check proofreading feature and is aimed primarily at students working on essays and papers.

Small SEO Tools Plagiarism Checker is a free online tool that scans written content against billions of web pages, academic papers, and published articles to flag possible duplication. Users can paste text, upload a document, or submit a URL, and the tool uses AI-assisted matching to catch both exact copies and paraphrased or reworded passages. Results include a similarity percentage, source-by-source breakdown, and a downloadable PDF or Word report.

The free tier covers checks up to 1,000 words without requiring an account, while paid plans remove the word cap and add features like API access and LMS integration. It supports over 25 languages and is aimed at students, teachers, bloggers, and content teams who need a fast, no-signup way to check originality before publishing or submitting work.

SafeAssign is a plagiarism prevention tool built directly into Blackboard Learn, the learning management system from Anthology (formerly Blackboard Inc). It compares student assignments against a Global Reference Database of more than 15 million papers, institutional archives of past submissions, general internet content, and the ProQuest ABI/Inform Journal Database. Instructors receive an Originality Report that highlights matching text, links to the source, and shows an overall similarity score.

SafeAssign is not sold as a standalone product; it comes included with a Blackboard Learn license, so pricing is set through an institution's Blackboard contract rather than public consumer pricing. It supports common file types including DOCX, PDF, and PPTX, and instructors can configure multiple submission attempts and use the URL Adder tool to compare against specific external sources.

Compilatio is a plagiarism and AI content detection platform based in France, used by schools, universities, and editorial professionals. It compares submitted documents against billions of indexed sources to flag exact matches, paraphrasing, and cross-language similarity, and its AI detector flags text likely produced by tools such as ChatGPT, Gemini, and Claude. Reports show a side-by-side view of the document and matched sources, and correctly cited passages can be excluded from the similarity score.

Compilatio offers separate products for teachers (Magister and Magister+), students (Studium), and professional writers (1D345 Copyright). Students buy one-time credit packs starting at 4.99 euros, while institutions and professionals get custom quotes. It integrates natively with Moodle, Canvas, Brightspace, Blackboard, and Microsoft Teams, and keeps document data on GDPR-compliant servers in France.

Trinka AI is a privacy-first grammar checker and writing assistant built specifically for academic and technical writing. Beyond standard grammar, spelling, and punctuation checks, it corrects thousands of advanced errors around scientific tone, word choice, and sentence structure, and applies style-guide-based corrections for APA, AMA, ACS, AGU, and IEEE formats. It also includes a paraphrasing tool, citation checker and formatter, journal finder, and built-in plagiarism and AI content detection scoring.

Trinka offers a free Basic plan alongside paid Premium, Premium Plus, and Confidential Data tiers, the last built for sensitive research needing instant data deletion and no AI training on content. Made by Crimson AI's Enago brand in India, it is used by researchers at institutions such as MIT, Stanford, and Princeton, and is available as a web app, Windows desktop app, and browser extension.

Plagramme is a plagiarism and AI content checker that scans against a database of more than 80 million academic articles and can detect translated plagiarism, where content has been copied and then machine translated into another language. Reports use color coded highlighting to distinguish properly cited text from likely plagiarism, and the AI detector provides a sentence level breakdown of suspected AI generated passages. The platform supports well over 100 languages and offers add on services for plagiarism removal and expert rewriting.

Pricing runs on monthly credit subscriptions, with a Basic plan at $14.95 per month for 10,000 credits, a Student plan at $29.95 per month for 30,000 credits with priority support, and a PRO Unlimited plan at $299.95 per month. Every account gets one free full document score check, and verified educators can access a larger free monthly allowance.

ProWritingAid is a writing improvement platform combining grammar and style checking with more than 25 in depth reports covering readability, sentence variety, repeated words, and cliches. AI powered tools called Sparks can rephrase text, adjust tone, or suggest ideas to overcome writer's block, while Manuscript Analysis and a Virtual Beta Reader feature give authors technical and subjective feedback on full length books. It integrates with Microsoft Word, Google Docs, and Scrivener, and supports real time collaboration with comments.

A free plan covers short 500 word checks, while paid Premium and Premium Pro plans unlock unlimited word counts and report runs, starting around $30 and $36 per month respectively, with substantial discounts for annual billing. A one time Lifetime plan is also available for users who prefer to avoid a recurring subscription.

PlagiarismRemover.AI is an AI-powered platform that rewrites copied or AI-generated content to remove plagiarism while preserving the original meaning, structure, and readability. Instead of simple word swapping, it produces context-aware rewrites that read naturally and are designed to pass major plagiarism and AI-detection tools.

It handles essays, research papers, reports, blog posts, marketing copy, and more, supports 16 languages, and includes an AI humanizer for refining machine-generated text. Because it runs in the browser and is optimized for mobile, users can clean up content on any device without installing software. A free tier makes it accessible to students, writers, educators, and professionals who need original, submission-ready content.