Shortlist by what you need
Start here if you know why you are leaving Plagiarisma.
Want the closest match?
SmodinMost similar to Plagiarisma in what it does, its category and its price.
Visit (opens Smodin in a new tab)Need a free plan?
QuillBotHas a free plan, rated 4.5 out of 5.
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ProofWrite AIFrom $9.99/mo, the lowest starting price here.
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WriterBuddyRated 3.7 out of 5 in our review, against 3.2 for Plagiarisma.
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At a glance
Green means better than Plagiarisma, red means worse. Prices are starting prices per month.
| Tool | Our rating | Starts at | Free plan | Best for | Compare |
|---|---|---|---|---|---|
 PlagiarismaBaseline | 3.2 | Free | Yes | Free online plagiarism checker with an AI content detector, an AI paraphrasing tool and an AI essay writer. | |
| Smodin | 4.2+1.0 | $10/mo | Yes | A grab-bag of writing utilities rather than one flagship feature | vs Plagiarisma |
 Undetectable AI | 3.2Same | Free | Yes | Detects AI content across text, image, audio and video, and also rewrites text to evade detection. | vs Plagiarisma |
 GPTinf | 3.5+0.3 | $19/mo | No | A paraphrasing engine that rewrites AI-generated text to read as human-written. | vs Plagiarisma |
| WriterBuddy | 3.7+0.5 | Free | Yes | 40+ academic writing tools in one place - co-writer, plagiarism checker, citation generator (MLA/APA/Chicago), ChatPDF - across 25+ languages. | vs Plagiarisma |
| ProofWrite AI | 3.9+0.7 | $9.99/mo | Yes | Rewrites AI text and checks it against seven detectors, all in one pass | vs Plagiarisma |
 Netus AI | 3.6+0.4 | $30/mo | Yes | AI paraphrasing and humanizing tool that rewrites text to read as human-written and pass AI detection. | vs Plagiarisma |
 JustDone | 2.7−0.5 | Not listed | No | Eleven student writing tools, two of which cancel each other out. | vs Plagiarisma |
| QuillBot | 4.5+1.3 | $10/mo | Yes | Started as a paraphraser, grew into a full writing suite | vs Plagiarisma |
The alternatives in detail
In order of how closely each one matches Plagiarisma.
Smodin
4.2$10/mo
vs Plagiarisma+1.0
A grab-bag of writing utilities rather than one flagship feature.
- Multi-mode paraphrasing tool
- AI content detector
- Plagiarism checker
Covers many unrelated writing tasks in one account
No single feature matches dedicated specialist tools
Undetectable AI
3.2Free
vs PlagiarismaSame
Detects AI content across text, image, audio and video, and also rewrites text to evade detection.
- AI text detection with flagged sections
- Image, audio and video AI detection
- Fake PDF detector
Detection across image, audio and video, not just text
Ships a humanizer for evading detection, with students among named users
GPTinf
3.5$19/mo
vs Plagiarisma+0.3
A paraphrasing engine that rewrites AI-generated text to read as human-written.
- Rewrites AI-generated text using a non-AI algorithm targeting perplexity and burstiness
- Eight distinct rewrite modes for different tone and style outcomes
- Built-in AI detector that scores text for AI-pattern probability
Addresses detection and rewriting in one interface instead of two separate tools
Independent tests have shown it failing to bypass detectors like GPTZero in some cases
WriterBuddy
3.7Free
vs Plagiarisma+0.5
40+ academic writing tools in one place - co-writer, plagiarism checker, citation generator (MLA/APA/Chicago), ChatPDF - across 25+ languages.
- Co-Writer: brainstorming, autocomplete, grammar checking
- Citation generator: MLA, APA, Chicago formats
- Plagiarism checker and AI content detector
Covers the full academic writing workflow, not just drafting
40+ tools means real exploration to find the right one for a task
ProofWrite AI
3.9$9.99/mo
vs Plagiarisma+0.7
Rewrites AI text and checks it against seven detectors, all in one pass.
- Built-in verification against named AI detectors including Turnitin, GPTZero, and Copyleaks
- Eight distinct writing modes tuned to context, including Academic, Formal, and Blog
- Meaning-preservation keeping original facts and citations intact
Detector verification built into the same workflow, not a separate tool
More words per month require a paid plan
Netus AI
3.6$30/mo
vs Plagiarisma+0.4
AI paraphrasing and humanizing tool that rewrites text to read as human-written and pass AI detection.
- AI Detection Bypasser that rewrites flagged text to read as human-written
- Paraphrasing engine covering 36 languages with adjustable tone and style
- Built-in AI content detector for checking text before publishing
Free Starter tier lets new users test output quality before paying
Reported team size is tiny (around one employee), raising questions about long-term support capacity
JustDone
2.7Not listed
vs Plagiarisma−0.5
Eleven student writing tools, two of which cancel each other out.
- Plagiarism checker and citation generator
- Summariser, paraphraser and grammar checker
- AI chat that reads PDFs and websites
Most of the toolkit is ordinary, useful study software
Ships an AI humanizer beside an AI detector, defeating both
QuillBot
4.5$10/mo
vs Plagiarisma+1.3
Started as a paraphraser, grew into a full writing suite.
- Multi-mode sentence and paragraph paraphrasing
- Grammar and clarity checking
- Text summarizer for long source material
Paraphrasing engine is genuinely strong and the tool's original focus
Heavy student association raises academic-integrity questions
FAQ
Questions people ask
Is Plagiarisma free?
Plagiarisma has a free plan.
What is the best free alternative to Plagiarisma?
QuillBot is the highest-rated alternative here with a free plan (4.5 out of 5). Other free options: Smodin, ProofWrite AI, WriterBuddy.
What is the cheapest alternative to Plagiarisma?
Among paid plans, ProofWrite AI has the lowest starting price (from $9.99/mo). If you need it free, start with QuillBot.
How did you pick these alternatives?
We match tools on what they do, their category and their price, using the details in our directory. Ratings come from our reviews and reader reviews.