Scribbr

What is Scribbr?

Scribbr is an academic-writing platform, part of Chegg, best known for its citation generators and human proofreading services. Its free AI Detector checks up to 1,200 words per submission with no signup and no usage limit, flagging text likely written by ChatGPT, Gemini, or Copilot.

For deeper checks, the paid Plagiarism Check compares up to 25,000 words against academic and web sources using the same technology many universities use, and bundles in a premium AI detector, a self-plagiarism checker, and a one-time AI proofreader pass. Plagiarism Check is billed per document rather than as a recurring subscription.

Key features

• Free, unlimited AI-text detector for ChatGPT, Gemini, and Copilot-style writing
• Distinguishes human-written, AI-generated, and AI-refined (edited) text
• Paid Plagiarism Check scans up to 25,000 words against academic/web sources
• Bundle includes a premium AI detector, self-plagiarism checker, and AI proofreader pass
• Paragraph-level feedback for more detailed AI-detection analysis
• Uses the same plagiarism-detection technology adopted by many universities

How to get started

1. Paste up to 1,200 words into the free AI Detector for a quick check
2. For longer or higher-stakes documents, purchase a Plagiarism Check by document size
3. Upload the full document for the combined plagiarism + AI + self-plagiarism scan
4. Review the similarity report and AI-probability score
5. Revise flagged sections before submitting

Scribbr pricing

Scribbr's AI Detector is free and unlimited for texts up to 1,200 words. The Plagiarism Check is a one-time, per-document purchase: $19.95 for up to 7,500 words, $29.95 for 7,500–50,000 words, and $39.95 for 50,000+ words, with no recurring subscription.

Our take: Sells plagiarism checking as a one-time, per-document purchase rather than a subscription, which suits students who only need a handful of checks per year.

Prices verified 2026-09. Plans change often — confirm on the official site above before you buy.

Use cases

• Students verifying a thesis or essay is original before submission
• Graduate students checking a dissertation chapter against prior published work
• Teachers spot-checking whether a submission was AI-generated
• Writers confirming they haven't accidentally reused their own previously published text

Scribbr vs. alternatives

FAQ

Is Scribbr free to use?

Scribbr's plans: Free AI detector; Plagiarism Check $19.95–$39.95/doc. Pricing and free-tier limits change over time, so check the official site above for the latest details.

What is Scribbr used for?

Free AI-text detector plus a premium, per-document plagiarism check that also screens for AI-generated and AI-refined writing.

Who is Scribbr best for?

Scribbr is a good fit for students verifying a thesis or essay is original before submission, or graduate students checking a dissertation chapter against prior published work.

What are the alternatives to Scribbr?

Commonly compared alternatives include GPTZero, Copyleaks, and Duplichecker, see the comparison above for how they differ.

How much does Scribbr cost?

Scribbr's AI Detector is completely free. Its Plagiarism Check (which also includes premium AI detection) is a one-time purchase priced by document length: $19.95, $29.95, or $39.95, with no monthly subscription.