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Plagium

What Plagium is
Plagium is a text-analysis service that compares submitted writing with public, private, proprietary and third-party sources to find similarities. Its plagiarism reports link to original sources, while a separate AI Detector uses statistical and probabilistic analysis to identify patterns associated with AI-generated writing. Deep Search accepts Microsoft Word, PDF and native text files. Document workflows include Google Drive integration and a Google Docs add-on; business offerings can integrate with CRM, ERP and document-management systems. Plagium offers web, Android and iOS access, plus API access for institutional users. Its free account includes five searches per day and a 4,000-character limit, but excludes Deep Search and API access. Other plans are listed, but prices are not provided. The company describes its audience as including educational institutions, publishers, editors, businesses, researchers and compliance teams. Reports are automated estimates, not definitive proof, and may miss unpublished, private or non-indexed material. Users retain ownership of submitted content, which is processed for analysis, reporting and service improvement.
Who it suits
Plagium may suit educators, publishers, editors, researchers and compliance teams checking text for similarities or AI-associated writing patterns. Businesses seeking integrations or institutional API access may also consider it.
What it does well
- Free account includes five daily searches.
- Similarity reports link to original sources.
- Deep Search accepts Word, PDF and text files.
- Google Drive and Google Docs workflows are listed.
- Institutional tier includes API access.
What to know first
- Free searches are limited to 4,000 characters.
- Free account excludes Deep Search and API access.
- Reports may miss private or non-indexed content.
- Reports are estimates, not definitive proof.
Limits
The Free account allows five daily searches, caps each free search at 4,000 characters, and excludes Deep Search and API access. Reports are automated estimates, and private, unpublished or non-indexed content may not be detected.
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| Free | 2 searches/day without sign-in · 5/day with account · 2,000 characters per text · summary only · no deep search | Free |
| Free account | 5 free daily searches · 4000-character free-search limit · no Deep Search · no API access | Free |
| Institutional | from $1,200/year; invoice available · 6,000 shared credits/year · unlimited members · API · LMS integration · member management and reporting | $1,200 a year |
| Unlimited | billed monthly for selected period; six-month option shown · 500 shared checks/calendar month · texts up to 5,000 characters · quick plagiarism and AI checks included · deep search and overage use credits | $19.98 a month |
| Single document | one payment · From $2 for 1–5 pages · any length with price increasing by pages · plagiarism and AI checks · full report, PDF and share link | $2, paid once |
| Credit packages | credits never expire · From $7.95 · 1 credit per estimated 2,500-character page · quick, deep, AI and file search | $7.95, paid once |
| Prepaid plan | 5 free daily searches · 4000-character free-search limit · Deep Search · originality certificate · volume discount | On request |
| Institutions | Plagiarism detection · Deep Search · AI Detector · priority support · API access · sub accounts · volume discount | On request |
The first 8 of 9 plans, as plagium.com lists them, read 15 Oct 2026. The maker's own page has the final word. Every plan
Getting started
- Visit https://www.plagium.com/.
- Choose the Free account for five daily searches with a 4,000-character limit.
- Use Deep Search through a plan that includes it, or upload a Word, PDF or text file.
- Connect through Google Drive or use the Google Docs Add-on for document analysis.
- Institutions can select the institutional tier for API access and sub accounts.
Overview
Plagium is a text similarity checker with a separate detector for patterns associated with AI-generated writing. It suits people who need both kinds of screening, from individual document checks to institutional workflows. Its free searches make it accessible, but reports are estimates and the free account has tight limits.
Key features
Similarity checks compare submitted text with online sources and return matches with links to originals. Those links give editors, students and researchers a useful starting point for examining context. Coverage is web-only, so unpublished, private or non-indexed material may be missed; the result should not be treated as proof.
The separate AI Detector analyzes statistical and probabilistic writing patterns. That adds a distinct screening signal, but it cannot establish authorship on its own, especially when a result could affect an academic or editorial decision.
Deep Search accepts Word, PDF and text files. Google Drive integration and a Google Docs add-on support document-based workflows. Institutional access includes an API, with API v2 and v3 documentation; business solutions can integrate with CRM, ERP and document-management systems. These options make Plagium more relevant to organizations than to users seeking only a quick standalone check.
Business offerings describe encryption, access controls and auditing, alongside compliance with corporate regulations. Plagium says its data processing follows applicable laws including GDPR and Brazil's LGPD. Users retain ownership of submitted content, which the service processes for analysis, report generation and service improvement.
Pricing
Plagium is freemium. The Free account costs nothing and allows five searches daily, each limited to 4,000 characters. It excludes Deep Search and API access, so it is best for occasional short checks rather than document-heavy or integrated workflows.
The Monthly plan has custom pricing and includes 10 free daily searches, the same 4,000-character free-search limit, Deep Search, priority support, an originality certificate and volume discounts. The daily searches are a baseline, not a substitute for confirming the terms of paid usage; readers needing larger volumes should weigh the custom price against the added features.
The Prepaid plan also has custom pricing. It retains five free daily searches and the 4,000-character limit while adding Deep Search, an originality certificate and volume discounts. It omits the Monthly plan's priority support, making it a narrower fit for buyers who want expanded search options without that support benefit.
Institutions, also custom pricing, adds plagiarism detection, Deep Search, the AI Detector, priority support, API access, sub-accounts and volume discounts. It is the clearest fit for multi-user organizations, while individual users may not need its administrative and integration features.
Platforms
Plagium is available on the web, Android and iOS. Google Drive and Google Docs support document workflows, while institutional API access and business integrations address organizational systems.
Who it's for
Plagium is aimed at educational institutions, publishers and editors, companies, researchers and compliance teams. Individuals who want occasional similarity and AI-pattern screening can start with the free account, but its character cap and lack of Deep Search limit more demanding work. Organizations may benefit from its document integrations, API and sub-accounts, provided they treat automated results as prompts for review rather than final judgments.
Pros and cons
- Pros: Similarity reports link to original sources, helping users investigate matches rather than just see a score.
- Pros: A separate AI Detector, file uploads and Google document integrations cover more than one checking workflow.
- Pros: Institutional API access, sub-accounts and business-system integrations can support organizational use.
- Cons: Web-only coverage can miss private, unpublished and non-indexed material.
- Cons: The free account caps searches at 4,000 characters and excludes Deep Search and API access.
- Cons: Automated similarity and AI reports are estimates, so consequential decisions need further review.
Alternatives
Noplag is worth considering for users who want a free 2,500-word check, public web and Common Crawl coverage, or platform options including self-hosting; its free plan allows three checks per month.
PlagAware may suit users prioritizing monitored URLs and a Content Protection Banner, with a free allowance of 10 pages per month and up to 30 monitored URLs.
Plagiarisma is an option for someone seeking a free Windows desktop plagiarism checker.
Proofademic may fit readers focused on multilingual AI detection, plagiarism checking and report export, with a free 1,000-word offer and a three-day trial.
SmallSEOTools Plagiarism Checker offers a free scan of up to 1,000 words and may suit shorter checks.
PrePostSEO Plagiarism Checker is another freemium option for readers who want Android, iOS, desktop and web platform support.
Check-Plagiarism may be a better fit for buyers comparing annual word and page allowances or a separate API plan.
Copyleaks AI Detector is an alternative for readers seeking AI and plagiarism detection with support for more than 30 AI-detection languages.
For broader comparisons, see AI Plagiarism Checkers and Plagiarism Detection Software.
Verdict
Plagium is a sensible choice for individuals and organizations that want similarity checks alongside a separate AI-pattern screen, particularly when document workflows or institutional integrations matter. Its source links and organizational options are useful strengths, but web-only coverage, short free searches and estimate-based reports set clear boundaries. Choose it when those signals support a human review; look elsewhere if you need wider source coverage or a definitive authorship judgment.
Verdict
Plagium combines text similarity checking with a separate AI Detector and supports several document workflows. Readers should account for the free plan's limits and treat reports as estimates rather than proof.
Questions
Does Plagium have a free plan?
Yes. Its Free account costs nothing and provides five free daily searches with a 4,000-character free-search limit.
Which platforms does Plagium support?
Plagium lists Android, iOS and web.
Does Plagium integrate with Google tools?
Yes. It lists Google Drive integration and a Google Docs Add-on.
Is API access available?
The institutional tier includes API access, and Plagium publishes API v3 and API v2 documentation.
Who makes Plagium?
The facts identify Plagium as the service name and say it was founded in 2006; they do not name a separate maker.
Are Plagium reports definitive proof?
No. Reports are automated estimates, and private, unpublished or non-indexed content may not be detected.
Facts from Plagium's own pages
- AI detection
- Plagium provides a separate AI Detector based on statistical and probabilistic analysis of writing patterns. · plagium.com, 30 Sept 2026
- AI detector
- The AI detector reports a likelihood of machine authorship and highlights mixed documents section by section. · plagium.com, 15 Oct 2026
- API
- The institutional tier includes API access, and Plagium publishes API v3 and API v2 documentation. · community.plagium.com, 30 Sept 2026
- API availability
- API access is restricted to the Institutional plan rather than individual free, prepaid or monthly plans. · plagium.com, 15 Oct 2026
- API endpoints
- API v3 documents endpoints support text creation, file upload, document retrieval, result retrieval and remaining-credit checks. · community.plagium.com, 15 Oct 2026
- API extensibility
- API v3 accepts webhooks, metadata and sub-account user IDs, and the documentation includes Node.js examples. · community.plagium.com, 15 Oct 2026
- Company facts
- LinkedIn lists New York headquarters, private ownership, 2–10 employees and a 2006 founding year. · linkedin.com, 15 Oct 2026
- Company history
- Plagium says it was founded in 2006 and that millions of users check documents and academic articles each year. · plagium.com, 30 Sept 2026
- Company identity
- LinkedIn identifies Plagium as a service of Septet Systems Inc. · linkedin.com, 15 Oct 2026
- Crunchbase profile
- Crunchbase lists Plagium as a private, for-profit New York company with 1–10 employees and no disclosed founding year. · crunchbase.com, 15 Oct 2026
- Data retention claim
- The About page says documents are processed, deleted on schedule and not added to the comparison index. · plagium.com, 15 Oct 2026
- Documentation
- The knowledge base covers account security, billing, plagiarism reports, AI-detector limitations, API authentication, usage limits, endpoints and webhooks. · community.plagium.com, 15 Oct 2026
- Document comparison
- Users can compare uploaded files against their own documents through File Search. · plagium.com, 15 Oct 2026
- Enterprise integration
- Business solutions integrate with existing corporate systems including CRM, ERP and document-management platforms. · plagium.com, 30 Sept 2026
- File support
- Deep Search supports uploads of Microsoft Word, PDF and native text files. · plagium.com, 30 Sept 2026
- Founded
- 2006 · plagium.com, 28 Sept 2026
- Google integrations
- The service lists Google Drive integration and a Google Docs add-on. · getapp.com, 15 Oct 2026
- Google Workspace listing
- Google Workspace Marketplace lists a free Plagium add-on made by Septet Systems that works with Google Docs. · workspace.google.com, 15 Oct 2026
- Headquarters
- New York, USA and France · plagium.com, 28 Sept 2026
- Integrations
- Plagium lists Google Drive integration and a Google Docs Add-on for analyzing documents. · plagium.com, 30 Sept 2026
- Language coverage
- The company says Plagium analyzes more than 40 languages and provides four interface languages. · plagium.com, 15 Oct 2026
- Licence and ownership
- Plagium describes its software, interface and technical structure as property of Plagium or its licensors; no open-source licence is stated. · plagium.com, 15 Oct 2026
- Limit: detection accuracy
- A Trustpilot reviewer estimated plagiarism detection at only 50–60% accuracy and rated the AI detector worse than competitors. · uk.trustpilot.com, 15 Oct 2026
- Limit: independent test
- PlagiarismChecker.net reported unstable behavior, confusing pricing/search choices, no file upload in its test and detection in three of six test documents. · plagiarismchecker.net, 15 Oct 2026
Where Plagium stands on Freedom251
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