Visibility in this ranking can be paid for. Payment gives a vendor more visibility, higher up on the review pages; it never adds a vendor, and it never changes a word of the review. The largest vendors in plagiarism checkers
cannot hold places 1 to 3. Places 1 to 3 go to challengers, vendors outside the best-known brands in a category,
wherever the category has them; the established names follow from place 4 in their ranked order. How it works: placement disclosure ·
editorial process.
The 12 tools, reviewed
#1 Plagramme
Multilingual plagiarism and AI checker with word-based plans · Lithuania · plagramme.com
Published prices Cross-language matching No comparison database
Plagramme earns first place on how much a single word allowance buys. The pricing page shows three tiers on a monthly or annual toggle, each charging one credit per word for the plagiarism check, the AI check and the cross-language check, so a student can see the cost of a chapter before paying.
- Pricing: Per user / month. Basic is $14.95 a month for 10,000 credits, Student is $29.95 for 30,000, PRO Unlimited is $299.95. Free plan: free plan.
- Best for: Students and editors working in several languages
- Strengths: Plagiarism check; AI detection; Cross-language plagiarism.
Where it falls short
Running all three check types on one file consumes three times the credits, so a 10,000-word Basic allowance is one long essay, not ten.
Wrong for
A university that needs a campus license, grade-book integration and a corpus of past submissions.
Visit Plagramme →
#2 PlagAware
German plagiarism scanner billed per page or per licence · Germany · plagaware.com
Servers in Germany Prepaid pages Text monitoring
PlagAware takes second place because a buyer can find out nearly everything without a sales call. The legal notice names PlagAware GmbH in Neu-Ulm, the data page says checks run exclusively on servers in Germany, and the pricing page lists three models: prepaid pages with no subscription, a yearly volume license for regular use and a fixed-price educational license.
- Pricing: Per page / credit. Prepaid scans start at EUR 12.99 for 100 pages, volume licenses from EUR 79 a year, educational licenses from EUR 189 a year. Free plan: free plan.
- Best for: Buyers who want EU hosting and prepaid pages
- Strengths: Plagiarism scan; ScanCredits per page; Text monitoring.
Where it falls short
Billing by the page means a dense page and a sparse one cost the same, so the pricing rewards long layouts.
Wrong for
A team that needs AI-text scoring or a sleek reviewer workflow.
Visit PlagAware →
#3 Viper
Pay-as-you-go plagiarism and AI checker online · United Arab Emirates · scanmyessay.com
Pay as you go 10 billion sources Google Drive import
Viper is third because it asks for so little commitment. The pricing page lists seven bundles and a per-250-word and per-1,000-word rate for each, falling from £2.00 per 1,000 words at the smallest pack to £0.48 at the largest, with no monthly fee.
- Pricing: Usage-based. Credits are bought in bundles: 10 credits for GBP 5.00 up to 1,000 credits for GBP 119.95, each credit scanning up to 250 words, with no subscription. Free plan: none.
- Best for: Students who scan a few papers a year
- Strengths: Plagiarism check; AI detection; Originality report.
Where it falls short
The operator is registered in the United Arab Emirates, not the UK its pound prices suggest, and its own pages say its essay writers are checked with Viper, which sits awkwardly in a school setting.
Wrong for
A school that needs a signed data-processing agreement with an EU entity.
Visit Viper →
#4 Quetext
Plagiarism and AI checker with word-based plans · United States · quetext.com
Published prices Bulk upload API and MCP
Quetext sits fourth on pricing clarity. The pricing page lists a free tier, an Essential tier at 100,000 words with 20-file bulk upload, and a Professional tier at 200,000 words and 100 files, and says business plans scale by words instead of seats.
- Pricing: Per user / month. Free covers 1,000 words. Free plan: free plan.
- Best for: Freelancers and small teams scanning web copy
- Strengths: DeepSearch plagiarism check; AI content detector; Bulk upload.
Where it falls short
The privacy policy permits use of submitted content for AI training, fine-tuning and evaluation unless you opt out by email, and the opt-out does not reach aggregated data or models already trained.
Wrong for
A university or a publisher that cannot accept a default training clause on manuscripts.
Visit Quetext →
#5 Compilatio
French plagiarism and AI detection suite for schools · France · compilatio.net
Quote only Altered-text detection LMS and SSO
Compilatio ranks fifth because it covers the school workflow without being the category's default. Its home page describes three products: Magister for teachers, Studium for students and Gingo for assignment creation and tracking, with plagiarism detection, AI detection and an altered-text detector that targets character swaps.
- Pricing: Quote only. Teacher and school products are priced on request after a demo; the student-facing Studium product opens with a free account. Free plan: none.
- Best for: Teachers and schools in French-speaking education
- Strengths: Plagiarism detector; AI detector; Altered text detection.
Where it falls short
A department head cannot compare cost until a demo is booked. Classrooms are the design center, so a content team that wants URL batches or site monitoring is outside what it was made for.
Wrong for
A freelance editor or a publisher who needs per-search billing.
Visit Compilatio →
#6 Copyscape
Web plagiarism search billed per search · Gibraltar · copyscape.com
Per-search billing Batch search Copysentry monitoring
Copyscape is sixth because it does one job and prices it by the unit. Its product page says Premium checks pasted text, uploaded PDF or Word files and whole sites, with Batch Search covering up to 10,000 pages in one operation and an API for scripts. Cases of copying can be logged with your response.
- Pricing: Usage-based. Billing is per search: a Premium search runs about 3 cents up to 200 words, with a cent added per extra 100 words, plus a monthly monitoring plan and a free comparison tool. Free plan: free plan.
- Best for: Publishers and SEO teams checking web copy
- Strengths: Web plagiarism search; Batch search of 10,000 pages; API.
Where it falls short
Only public web pages are searched, so a paper copied from a closed school archive passes. The interface is bare: no LMS plugin, no shared dashboards, no annotation.
Wrong for
A university needing a submissions archive and grade-book links should read the Turnitin or Compilatio entries.
Visit Copyscape →
One-time license Windows desktop 250+ languages
Plagiarism Checker X lands seventh as the only product here that still offers a lifetime purchase.
- Pricing: Open source + paid tiers. Cloud plans are $14, $29 and $99 a month. Free plan: free plan.
- Best for: Individuals who prefer a one-off license
- Strengths: Plagiarism check; AI detection; Side-by-side comparison.
Where it falls short
The pricing page shows two product lines at once, a desktop program and a cloud workspace, and it is not obvious which comparison index each uses. The privacy page does not say what happens to scanned documents.
Wrong for
A Mac or Chromebook user who wants the desktop program, or a school that needs an LMS connection.
Visit Plagiarism Checker X →
#8 Turnitin
Institutional similarity and AI writing detection · United States · turnitin.com
Quote only Student-paper corpus LMS integrations
Turnitin is eighth only because the largest incumbents cannot take the top three. It is the product most universities mean by plagiarism software: Feedback Studio, Similarity and iThenticate for publishers, with Clarity as its newer writing-process product. Its product pages describe an LMS-first rollout, a Flags panel and detection of AI writing and AI paraphrasing.
- Pricing: Quote only. Institutional quotes only; the Similarity product and the Originality bundle with AI writing detection are priced per school, never on a page. Free plan: none.
- Best for: Universities needing LMS and a submission archive
- Strengths: Similarity report; Flags panel; AI writing detection.
Where it falls short
No figure is published, and the AI layer is priced on top of similarity. Submitted papers may join a repository that the vendor controls, so retention and deletion must be settled by contract.
Wrong for
An individual, a small publisher or a freelancer buying one scan.
Visit Turnitin →
#9 Inspera Originality
Norwegian similarity checker for assessment platforms · Norway · inspera.com
Quote only Translation similarity LMS support
Inspera Originality is ninth because it is strong inside its own platform and closed outside it. Its page describes contextual similarity that finds paraphrase and semantic overlap, text matching in more than 30 languages, translation similarity in up to three extra languages, a sentence-level likelihood for AI authorship, and detection of hidden text, character swaps and text sent as an image.
- Pricing: Quote only. Sold through a demo request only, either with Inspera Assessment or connected to an existing LMS; nothing is priced on the page. Free plan: none.
- Best for: Institutions already on the Inspera stack
- Strengths: Similarity detection; Contextual similarity; Translation similarity.
Where it falls short
The page lacks any price, corpus size or accuracy measure, so the evaluation rests on a brochure. Individuals cannot register and scan.
Wrong for
A small business or individual who needs a scan today.
Visit Inspera Originality →
#10 ProWritingAid
Editing assistant with a paid plagiarism add-on · United Kingdom · prowritingaid.com
Add-on pricing Editing suite Student discount
ProWritingAid is tenth because plagiarism is a purchase beside the editor, not the product. The pricing page marks the plagiarism check as an additional cost in all three plan columns and links to a separate Buy Plagiarism Checks page, and the company offers a 25 percent student discount on yearly plans and free premium access for educational organizations.
- Pricing: Per user / month. The plan grid lists the plagiarism check as additional cost on every plan. Free plan: free plan.
- Best for: Authors already paying for ProWritingAid
- Strengths: Plagiarism check; Grammar and style reports; Combo report.
Where it falls short
We could not see the price of a check, its source list or how long documents are kept, since the plagiarism page was not readable in our fetch.
Wrong for
An institution, a web publisher or a teacher scanning many files.
Visit ProWritingAid →
#11 Copyleaks
Plagiarism, code and AI detection suite with API · United States · copyleaks.com
API Code plagiarism AI detection
Copyleaks is eleventh because the breadth is real and the verification is thin. The vendor lists text plagiarism, source-code plagiarism, AI text and image detection, a grammar API, a citation checker and a Cloud Private Hub, with software development kits in several languages.
- Pricing: Quote only. Pricing could not be read because a bot check blocked the page; no figure is stated here. Free plan: free trial.
- Best for: Teams that need an API and code checks
- Strengths: Plagiarism in text; Code plagiarism; AI text detection.
Where it falls short
A bot check stopped us reading the pricing, company and terms pages, so cost, registered office and any training clause are unconfirmed. Many products and credit types may confuse a buyer who only wants to scan a file.
Wrong for
A student or small editor who wants a plain per-scan price on a page.
Visit Copyleaks →
#12 Grammarly
Writing assistant with a plagiarism check · United States · grammarly.com
Writing assistant ProQuest sources Browser extension
Grammarly takes twelfth in a list judged on checking depth, because it is a writing assistant that includes a scan. Its plagiarism page says the check compares text against billions of web pages and ProQuest's academic databases, flags sentences, names sources and calculates an originality score, with citation suggestions to fix a flagged passage.
- Pricing: Per user / month. Free costs EUR 0. Free plan: free plan.
- Best for: Writers who already use Grammarly
- Strengths: Plagiarism detection; AI text detection; Authorship tracking.
Where it falls short
Checking is a side function, and nothing we read states corpus size, sampling or method. Whether Free includes the scan is not said.
Wrong for
A school, a publisher or a content agency that needs to screen other people's work.
Visit Grammarly →
Questions and answers
What is the best plagiarism checker in 2026?
Plagramme ranks first of 12, best for students and editors working in several languages. PlagAware is second (buyers who want EU hosting and prepaid pages) and Viper third (students who scan a few papers a year). Places 1 to 3 go to challengers, vendors outside the best-known brands, wherever the category has them.
Is there a plagiarism checker that is free and actually usable?
Several give you a first scan at no cost. Plagramme offers free originality scores, PlagAware includes ten pages of checks with a free account, Quetext's free tier covers up to 1,000 words, and Plagiarism Checker X ships a Windows edition with a daily search limit.
Do plagiarism checkers keep the documents I upload?
It depends on the vendor, and the answer sits in the privacy policy, not the marketing page. Plagramme says it never adds files to a comparison database. PlagAware states that checked and reference texts are stored in German data centers.
How is a similarity percentage different from proof of plagiarism?
The percentage only counts matching text. Quotations, a bibliography, a standard legal clause or a template can all raise it without any copying.
What does a plagiarism check cost for one document?
Rough figures from published pages: Viper charges about £1.04 per 1,000 words at its 100-credit bundle, Copyscape bills three cents for the first 200 words plus one cent per extra 100, and PlagAware starts at €12.99 for 100 pages, which is about 13 cents a page.
Can a plagiarism checker find copying from another student's paper?
Only if the vendor holds those papers. A web-only search such as Copyscape cannot see closed archives. Turnitin's reference corpus includes student submissions, and Compilatio and Inspera offer institutional archives that a school builds up over time.
Do plagiarism checkers work in languages other than English?
Coverage varies. Plagramme lists cross-language matching, which compares text with sources in other languages. Plagiarism Checker X says it understands more than 250 languages.
Are there European plagiarism checkers with EU data hosting?
Yes. PlagAware is a German company, runs its checks on servers in Germany and publishes its imprint. Compilatio is French, Plagramme is operated by a Lithuanian company and its terms name Lithuanian courts, and Inspera is Norwegian.
Is Grammarly's plagiarism checker enough for a thesis?
For a first pass, often yes: its page says the check compares text with billions of web pages and ProQuest's academic databases. It is a writer's tool, though.
Which plagiarism checkers can scan a whole website?
Copyscape is the clearest answer: its Batch Search can check up to 10,000 pages in one operation, and Copysentry monitors pages for new copies on a schedule.
Should I pay for a plagiarism checker that also detects AI text?
Only if you will act on it. The AI score is a separate estimate and a different risk from copying, and several vendors bill it from the same word allowance.
