O
Detection
Accurate AI detector and plagiarism checker for content teams
AI DetectorPlagiarism CheckerContent Quality
Originality.ai checks text for AI-generated content and plagiarism, and adds readability, grammar, and fact-checking on top. It's built to stay accurate against the latest LLMs (GPT, Claude, Gemini, DeepSeek, Llama and more) and against AI paraphrasing tools like Quillbot, with team management, full-site scans, and an API for agencies and publishers.
- Best for
- Content teams, publishers, and agencies verifying freelance/outsourced writing for AI use and plagiarism before it goes live; also used by teachers checking student work.
- Pricing
- Free plan available (3 AI scans/day, 2,000 words/scan). Paid plans from $12.95/mo (Pro, 2,000 credits/mo) to $136.58/mo (Enterprise, 15,000 credits/mo).
Core features
- • AI Checker accurate on GPT, Claude, Gemini, DeepSeek, Llama, and more
- • Detects AI-paraphrased text (Quillbot, Grammarly-style edits)
- • Plagiarism Checker, Grammar Checker, Readability Checker, Fact Checker
- • AI Allowance to set how much AI content is acceptable
- • Deep Scan explains why text was flagged and how to edit it
- • Sentence-level highlights showing likely-AI sentences
- • Shareable PDF reports and scan history
- • Chrome/Firefox extensions, Google Classroom & Moodle plugins, API access
Use cases
- 1. Verifying freelance or outsourced writing before publishing
- 2. Checking student submissions for AI use and plagiarism
- 3. Auditing an entire existing website's content by URL
- 4. QA/QC workflows for content teams and agencies at scale
- 5. Fact-checking and readability review before publishing
How to use
Paste text, upload a file (docx/pdf/doc), or enter a URL to scan. Choose which checks to run (AI detection, plagiarism, readability, grammar, fact-check), then review the results — use Deep Scan and sentence highlights to see exactly what's flagged and how to edit it.
Pricing plans
Basic
Free
- • AI detection only, no subscription required
- • 3 scans per day
- • Limit of 2,000 words per scan
- • File upload (docx, pdf, doc)
Pro
$12.95/mo
- • 2,000 credits/month (1 credit = 100 words)
- • Full site scans from a URL
- • Team management, tag scans
- • Chrome extension
- • Standard support
Enterprise
$136.58/mo
- • Everything in Pro
- • 15,000 credits/month
- • 365 days scan history
- • API access
- • Dedicated Customer Success Manager, priority support
FAQ
Is there a free plan?
Yes — the Basic plan is free with no subscription required, offering 3 AI scans per day up to 2,000 words each.
Can it detect AI text that's been paraphrased?
Yes, Originality.ai is trained on adversarial data and actively tested against paraphrasing tools like Quillbot and Grammarly to catch AI-altered text.
Can I scan an entire website at once?
Yes, Pro and Enterprise plans support full-site scans — enter a URL and it scans the site's content for you.
Where it holds up
- Proven accuracy in third-party AI-detection studies, kept current against the latest LLMs
- Also flags AI-paraphrased text run through tools like Quillbot or Grammarly
- Bundles plagiarism, readability, grammar, and fact-checking in one scan
- Full-site scans by URL make auditing existing content fast
- Genuinely usable free tier (3 scans/day) with no subscription required
Where it falls short
- Free plan is capped at 2,000 words per scan and 3 scans a day
- Credits expire monthly rather than rolling over indefinitely
- API access and full scan history are Enterprise-only
