GPTZero

What is GPTZero?

GPTZero is an AI detector that estimates whether a piece of writing came from a large language model such as ChatGPT, Gemini, Claude or LLaMA. You paste text or upload a file and get a score for the whole document, plus sentence-by-sentence highlighting that shows why passages were flagged. Deep Scan adds a statistical breakdown of how each sentence affects the AI probability, and paid plans bring plagiarism checks, grammar feedback and source citations. Teachers and students are the main audience: Writing Reports for Google Docs show editing statistics and a replay of the writing process, and a Chrome extension called Origin scans pages as you browse. An API lets organizations add detection to their own tools. GPTZero says results should start a conversation rather than be used to punish anyone, since no detector is perfect. A free plan allows 10,000 words a month, and paid plans start at $10 per month.

Use cases

• Check text for AI-generated writing
• Highlight AI sentences in an essay
• Scan batches of student files
• Check documents for plagiarism
• Review a writing process in Google Docs
• Detect AI text through an API

Who it's for

• Teachers
• Students
• Educators and administrators
• Editors and publishers
• Hiring teams

Why use GPTZero

• Sentence-level highlighting shows which passages triggered the result, so a teacher has something concrete to discuss.
• Writing Reports record the drafting process in Google Docs, which gives students a way to show their own work.
• A free plan lets you try the detector before paying.
• One account covers the web dashboard, the Origin browser extension and an API for developers.
• Team plans start without a sales call and include shared credits and unified billing.

GPTZero features

• Document, paragraph and sentence-level AI detection
• Deep Scan with per-sentence probability analysis
• Sentence highlighting that explains why text was flagged
• Plagiarism scanning and source or citation generation
• Grammar check, AI vocabulary check and writing feedback
• Writing Reports for Google Docs with a video of the writing process
• Origin Chrome extension for scanning web pages
• Batch file upload and saved scan histories
• AI detection API with sample code in 17 languages
• Multilingual AI detection on Premium
• LMS integration on Professional

GPTZero integrations

• Google Docs
• Chrome
• LMS platforms

How to get started with GPTZero

1. Open the GPTZero dashboard and paste text or upload a file.
2. Run a scan to get an overall AI score for the document.
3. Review the sentence highlights, or run Deep Scan for a finer breakdown.
4. Check plagiarism or grammar if your plan includes them.
5. For students, use Writing Reports in Google Docs to show how a document was written.

GPTZero limitations

• The Free plan allows 10,000 words a month and up to 10,000 characters per scan
• Free scans are limited to 7 per hour
• Results can misclassify text in both directions and should not be used alone to punish students
• Accuracy rises with longer text and is lower at sentence level than document level
• Heavily edited AI text and procedural text can be misjudged

GPTZero pricing

Yes, GPTZero has a free plan. Paid plans start at $10 per month, according to the official pricing page on 24 Oct 2026.

GPTZero plans

• Free

  Free

  • 10,000 words per month
  • Basic AI Scan
  • One Advanced Scan
  • Origin Chrome extension

• Essential

  $10/month

  • 150,000 words per month
  • Plagiarism scanning
  • Grammar and writing feedback
  • AI Vocabulary Check

• Premium

  $16/month

  • 300,000 words per month
  • Advanced AI Deep Scan
  • Multilingual AI detection
  • Downloadable AI reports

• Professional

  Price on vendor site

  • Page-by-page scanning
  • LMS integration
  • Enterprise-grade security
  • Scans up to 150,000 characters

• Professional Team Plan

  Price on vendor site

  • Min 2 seats
  • 500,000 words per member per month
  • Shared team credits
  • Unified billing and seat management

Plans as listed on the official pricing page on 24 Oct 2026. Prices can change and may vary by country or exclude tax. Check the official pricing page.

GPTZero alternatives

The main GPTZero alternatives listed on Debuly are Originality.ai, Grammarly, Grammarly API, Lynote, QuillBot and ReText.AI. The table compares pricing and platforms; order is A–Z.

1. 

   Grammarly

   AI writing assistant that fixes grammar, adjusts tone, rewrites sentences and drafts text in the apps and sites where you write.

   WritingProductivityMarketing and SEO
   FreemiumVisit Grammarly (official site)
2. 

   Grammarly API

   REST APIs for Grammarly Enterprise and Education admins covering writing scores, usage analytics and license management.

   WritingDeveloper platforms
   Contact salesVisit Grammarly API (official site)
3. 

   Lynote

   AI humanizer and detector that rewrites AI-generated drafts into natural writing, checks them with AI scores, and offers a paid API.

   WritingDeveloper platformsProductivity
   FreemiumVisit Lynote (official site)
4. 

   Originality.ai

   AI content detector and plagiarism checker with fact, grammar and readability checks for publishers, agencies, writers and schools.

   WritingMarketing and SEOResearch and search
   FreemiumVisit Originality.ai (official site)
5. 

   QuillBot

   Writing assistant with a paraphraser, grammar checker, summarizer, AI detector and plagiarism checker for students and everyday writers.

   WritingProductivity
   FreemiumVisit QuillBot (official site)
6. 

   ReText.AI

   Online text tools for paraphrasing, summarizing, expanding, grammar checking and AI-text detection, with a premium tier and API.

   WritingDeveloper platforms
   FreemiumVisit ReText.AI (official site)

GPTZero FAQ

Sources & verification

Facts on this page come from the official sources below, each with the date we read it. Written by Debuly; the vendor did not review this page.

Image credits

• Logo: from gptzero.me · fetched 23 Oct 2026 · Vendor trademark, used only to identify the product; removed on request
• Cover: none collected yet, so a generated tile is shown.

Spot an error? Report an issue with this listing. We also remove a logo or image on the owner's request.