Most Accurate AI Detector

Our AI Detector By Originality.ai™, available for free below, is the Most Accurate AI Detector for GPT-5, ChatGPT, Claude 4, Gemini 2.5, Grok 3 and all other Popular AI writing tools.

Want to Show Your Writing is Your Own?

With our Chrome Extension you can watch a replay of how a document was created.

Want to Show Your Writing is Your Own?

With our Chrome Extension you can watch a replay of how a document was created.

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Trusted by Industry Leaders

Harvard UniversityThe GuardianThe New York TimesFlippaMotion InvestSurferDotdash meredithGDDiggity MarketingWriteraccessGMAlibaba.comWalmartAT&TAAReutersBusiness InsiderNeil Patel

How to use Originality.ai

Paste or Upload Text

Step 1

Paste or Upload Text

Login to Originality.ai and paste your text into the editor. You may also upload a PDF to check if a document was written by AI or enter a URL for scanning.

Select Scan Types

Step 2

Select Scan Types

Select your desired scan types like AI, Plagiarism, Content Optimization, Readability, Grammar OR Fact Checker to scan your text against.

Click Scan

Step 3

Click Scan

Click on the Scan button and get scores for each scan type with detailed explanations and sentence highlights wherever applicable.

Originality.ai identified As The Most Accurate AI Detector Across Multiple Studies

Most Accurate AI Checker

Results Shown

Accuracy comparison of AI text detection tools on AH&AITD

Percentage correct for GPT-4 papers

Mean accuracy at FPR=5% for detectors on non-adversarial outputs

Mean accuracy for ChatGPT-generated and AI rephrased articles

Mean AUROC of GPT-3.5 vs. human-written, GPT-4 vs. human-written, mixed human/GPT-3.5 vs. human-written, mixed human/GPT-4 vs. human-written, translated vs, human-written

Mean accuracy for (a) human vs. AI and (b) human vs. disguised

Originaltiy.ai

97.09

100

85

100

87.9

86.5

GPTZero

63.77

57

67

45

77.28

84.5

Writer

69.05

40

Not included

Not included

Not included

Not included

CopyLeaks

Not included

100

Not included

Not included

Not included

Not included

TurnItIn

Not included

100

Not included

62

Not included

Not included

Binoculars

Not included

Not included

80

Not included

Not included

Not included

FastDetectGPT

Not included

Not included

74

Not included

Not included

Not included

ZeroGPT

Not included

83

66

92

Not included

85

GPT-2 Output Detector

Not included

Not included

Not included

85

Not included

Not included

Sapling

66.66

33

Not included

Not included

75.92

Not included

Winston

Not included

Not included

71

Not included

Not included

77

GPTkit

55.29

Not included

Not included

Not included

Not included

Not included

Zylalab

68.23

Not included

Not included

Not included

Not included

Not included

SEO.ai

Not included

83

Not included

Not included

Not included

Not included

Scribbr

Not included

69

Not included

Not included

Not included

Not included

Grammica

Not included

62

Not included

Not included

Not included

Not included

Crossplag

Not included

69

Not included

Not included

Not included

Not included

OpenAI

Not included

40

Not included

Not included

Not included

Not included

IvyPanda

Not included

40

Not included

Not included

Not included

Not included

GPTRadar

Not included

31

71

Not included

Not included

Not included

Content at Scale

Not included

52

Not included

50

Not included

Not included

ContentDetector.ai

Not included

7

Not included

Not included

Not included

Not included

GLTR

Not included

Not included

63

Not included

Not included

Not included

RoBERTa-Base (GPT2)

Not included

Not included

59

Not included

Not included

Not included

RoBERTa-Large (GPT2)

Not included

Not included

57

Not included

Not included

Not included

RoBERTa-Base (ChatGPT)

Not included

Not included

45

Not included

Not included

Not included

LLMDet

Not included

Not included

35

Not included

Not included

Not included

Studies on "Do AI Detectors work?"

Benefits of Our Free AI Detector Chrome Extension

Check for AI Content on Any Website Quickly

Quick scan

Check for AI Content on Any Website Quickly

With our Chrome Extension you can check any webpage you are visiting to see if it is AI written text.

Quickly Check Content Using our Copy/Paste Window

Easy copy paste

Quickly Check Content Using our Copy/Paste Window

Easy-to-use copy and paste text window: check content in Google Docs or any web page in Chrome to check for AI or plagiarism.

Watch a Writer Write and Monitor for AI-generated copy

Identify Copy Paste

Watch a Writer Write

Peace of mind for writers and students. Watch a writer write the entire document with a sped up behind the scenes look and shareable report.

Features Our Enterprise and Education Customers Love

Security, Privacy, Controls & API

We understand the unique needs of high-volume web publishers, agencies, schools, and education institutions who need transparency at scale. Don’t risk the negative impacts of Google search traffic dropping or AI writing in student assignments.

Sign up now   ›
Team Management

Team Management

Add, remove and monitor usage of your organization's users. Assign roles as Admin, Manager or User to limit individual ability to access the whole set of features.

AI Checker API

AI Checker API

Reliable, Full-Featured, and Fast API Access. See the AI detection API your developers will love.

Your Text is Encrypted

Your Text is Encrypted

TLS 1.2 or higher is achieved with our end-to-end military grade 256 bit encryption. Your content is highly protected, even our back-end engineers can’t access it.

Data Not Used in Training

Data Not Used in Training

Optionally opt-in or opt-out of your data being used in future AI training.

A Complete QA/QC Solution

A Complete QA/QC Solution

Get a full suite of QA/QC features from plagiarism checking to fact checking and readability. Publish with integrity.

One-Click delete Scan History

1-Click Delete Scan History

Easily delete all your scan history in 1 click. Keep your scan and Originality reports history organized.

Sentence Level Highlighting

Sentence Level Highlighting

Our AI content detector will highlight sentences indicating the probability of whether or not each sentence was AI written or human written.

What Is the Best AI Detector Model for Your Needs?

Patented Industry Leading Models That Fit Your Use Case

The use of AI in content writing is nuanced. We have models that are tuned to your specific use case. Whether you allow AI editing or want NO AI to get past your review we have a model that is optimized for your approach to AI text detection.

Lite 1.0.1

For Writers & Editors

Lite 1.0.2

When you allow AI editing (think grammarly)

  • 99% accurate at detecting AI content.
  • 0.5% false positive rate.
  • Allows for some light AI editing.
  • Detects heavily AI-edited text.
Lite 1.0.1

For Students & Teachers

Academic

Best for education use cases

  • 99%+ accurate at detecting AI content.
  • <1% false positive rate.
  • Detect AI in academic writing.
  • Robust detection for AI-polished text.
Turbo

For Professionals

Turbo

Zero tolerance policy on use of AI

  • 99%+ accurate at detecting AI content.
  • 1.5% false positive rate.
  • Robust against AI-edited text.
  • Does not allow for AI editing.
Multi Language

For Non-English Texts

Multi Language

Optimized for 30 Languages

  • Including Spanish, Portuguese, French, German, Dutch, Arabic and many other languages.
  • Removes language barriers globally.
  • Automatically detects the language.

Features of our AI Detector for Writers & Students

Prove Your Work or Assignment is Original

Our industry-leading AI detector provides you with the ability to accurately identify AI content, correct accidental AI plagiarism, and share reports to show your writing is Original.

Sign up now   ›
Shareable Reports

Shareable Reports

Easily share the results. Show your text is Original with a shareable link.

Edit

Edit

Streamline editing in-app with our fully featured text editor and then scan again.

Export

Export

Easily export text with one-click copy pasting to Google Docs or Microsoft Word for further editing.

Highlighting

Highlighting

See what sections of the text is most likely to be identified as AI-generated.

Scan History

Scan History

See a complete history of all scans that you can reference in the future as needed.

PDF Report

PDF Report

Download a PDF report showing if the text is Likely AI or Original.

Key Originality.ai Features

Factual Accuracy

Factual Accuracy

  • Real-time fact checking; check the latest facts (no training date cutoffs)
  • Avoid AI hallucinations like the AI book scandal
  • Save time with context and source links to verify facts fast
  • More Accurate than GPT-5: Our fact checker outperformed existing LLMs in our latest testing
Plagiarism Checking

Plagiarism Checking

  • Identify global plagiarism with 99.5% accuracy
  • Surpasses competitors like Copyscape, Grammarly and Turnitin
  • Modern plagiarism detection
  • Catch copy-paste and complex plagiarism types like paraphrase and patchwork
  • Shareable report to prove that writing is original and authentic
Readability and Grammar Checking

Readability & Grammar Checking

  • The popular “aim for Grade 8 readability” target is wrong. Our readability scores are based on a modern study of what actually ranks well in Google!
  • Easily spot grammar and spelling issues and then refine copy in 1 click with ‘Fix issues’
  • Scale grammar and spelling checks with an API

Originality.ai is Built For…

Marketers, Writers & Publishers 

Marketers, Writers & Publishers 

Teachers & Students

Teachers & Students

  • Uphold integrity and transparency across: assignments, essays, coursework, papers
  • Moodle Plugin: easily check for AI content and plagiarism in Moodle LMS
  • Peace of mind for students with a Free Chrome Extension to ‘Watch a Writer Write’
  • Deep Scan: See why text is flagged as AI + how to ethically edit it, so your work is identified as original (not AI)!
Agencies & Enterprise

Agencies & Enterprise

  • Manage client & writer expectations for AI use
  • Integrate a process for AI detection, plagiarism checking, and factual accuracy at scale
  • Streamline editorial processes across teams with team management and report sharing

The Best AI Checker - Customers Love Originality.ai

Sam Saltis

Sam Saltis

Originality is a great tool for detecting AI content. The product has been invaluable for our content marketing team. Fernanda and the team are always very responsive and helpful. Highly recommend this product.

Miguel Maloney Thompson

Miguel Maloney Thompson

I have the opportunity to make sure that my writing is plagiarism-free, and with a lot of AI-generated content around, I can ensure my writing does not get flagged as just another to the bunch.

I do technical writing where there are only so many ways to describe concepts and ideas. However, Originality.ai gives me the opportunity to personalize my writing even more, which is an advantage. With some time, I can give my content a sense of uniqueness.

John Kohn

John Kohn

Reliable and trustworthy. Originality is always so quick to respond to my questions and lend a helping hand. It’s a very good tool for detecting ChatGPT use on academic papers, especially with the "view writing" feature which shows the text being typed by the student as they were typing it.

Stevie Lambert

Stevie Lambert

AI is accurate compared to free choices and the support staff like Ellie are very helpful. The interface is easy to use and shows a % chance of the work being AI. It’s also, nice that it shows what parts may be AI or not.

Aptidus

Aptidus

The service provided is exceptional, offering the most accurate and reliable AI detector available on the market. The customer support team is exceptionally responsive.

Gbas gbos

Gbas gbos

Originality's AI checker and plagiarism detector are absolutely phenomenal—by far the best I have used (yes, I used all of Winston, GPT zero, etc.). The Turbo model is CRAZY good! 

Vivek Pandey

Vivek Pandey

There are lots of similar AI detection tools available online but nothing comes even close to what they offer. I can't trust any other tools other than theirs. Have tried maybe 20-30 other websites and settled with them.

Yanmin Wang

Yanmin Wang

I had an excellent experience with the support team at Originality.ai. They were incredibly responsive and provided clear, detailed answers to all my questions. The explanations were thorough, and I now have a much better understanding of how the platform works and how my content is handled. 

The team was patient and professional and went above and beyond to ensure all my concerns were addressed. I truly appreciate their help and the top-notch customer service they provide. Highly recommended!

Canadian Law Student

Canadian Law Student

Originality.ai is the best tool on the market. I have used comparable services and this one is exceptional. It provides an accurate report with a match score which really helps writers/researchers adjust and improve their work. 

There are also advanced features such as paraphrase detection which are not available with any other comparable service. The features provided by Originality.ai are exceptional for users who want to avoid plagiarism and also improve their research process. I hope to continue using Originality.ai for many years to come.

John Willsdon

John Willsdon

This is a really helpful tool. Certainly the best of the AI detectors I tried. What makes it great is that you also get a bunch of other tools that are really helpful. The fact checker is awesome, it gives you feedback on whether or not points in your essay are factual or not by reading the source material in your citations.

Todd

Todd

I have been using this tool since the start! And it has saved me many times. Many times when checking clients' sites the problem was AI content or plagiarism.

Chris Swanson

Chris Swanson

When I hire writers, I want 100% human-written content. I depend upon Originality.ai to check this for me.

Dirk Berger

Dirk Berger

Originality.ai saved me from making a big mistake. I have written a book with the help of ChatGPT, 40% of my work is AI; 60% is human. It identified the AI, and now I am writing it all by myself. 88-100% human. Thank you Originality.ai.

Rob McTavish

Rob McTavish

I started to look for an easy tool to confirm my suspicions over some of the material being submitted by my students in first-year Communication courses. I found Originality.ai and tried it out. It worked so well that I actually tested it out with some material I created using AI as an example and sure enough, it perfectly determined which was my work, what was totally AI-written, and what was edited AI material.

Andrew Stevenson

Andrew Stevenson

Originality.ai has been remarkable in its ability to detect AI content. The customer service is also incredible in how thorough and responsive they are. Highly recommend this program.

Pieter Steenkamp

Pieter Steenkamp

I found Originality.ai to be the best AI detector. I use it for my student's assignments and recommend it to my colleagues.

JC Playz

JC Playz

Originality really lives up to the expectations, it's super reliable and has the best detector for AI. Now I can understand why so many people use it such as professionals.

Trish McLean

Trish McLean

Incredible experience. Excellent product. Very easy to use, thorough and informative. Brady was incredibly helpful on the chat. He carefully checked my document to see why it had a high score for AI and then explained it to me. He provided individualized advice on how to move forward. Excellent! Thank you Brady.

Joseph Bereber

Joseph Bereber

Customer service is top-notch. Not only are they super accommodating, they are also super helpful. The tools on Originality.ai are also incredibly accurate and very useful. I've had nothing but positive experiences using this service.

Peter Stuart

Peter Stuart

Originality.ai is by far the best AI detector tool. We have used other tools to detect AI in content but we have found that Originality.ai is by far the most accurate. This, combined with flexible payment plans to suit individual requirements and sharp customer support. Originality.ai is a no-brainer if you are looking for an AI detection solution.

In the Press

Most Trusted AI Detector by Industry Leaders

Harvard UniversityThe GuardianThe New York TimesFlippaMotion InvestSurferDotdash meredithGDDiggity MarketingWriteraccessGMAlibaba.comWalmartAT&TAAReutersBusiness InsiderNeil Patel
CNN

Jennifer Korn

How companies are embracing generative AI for employees…or not

Many prominent companies have entirely blocked internal ChatGPT use, including JPMorgan Chase, Northrup Grumman, Apple, Verizon, Spotify and Accenture, according to AI content detector Originality.AI, with several citing privacy and security concerns.

Read more ›
Politico

Ben Schreckinger

AI vs. public opinion

Originality.ai, a site that provides detection services for AI-generated content and plagiarism, published a convenient tracker that lists the 10 pending lawsuits against OpenAI and ChatGPT.

Read more ›
The Guardian

Betsy Reed

Mushroom pickers urged to avoid foraging books on Amazon that appear to be written by AI

Four samples from the books were examined for the Guardian by Originality.ai, a US firm that detects AI content.

Read more ›
The New York times

Steven Lee Myers & Tiffany Hsu

Another Side of the A.I. Boom: Detecting What A.I. Makes

More than a dozen companies have popped up to offer services aimed at identifying whether photos, text and videos are made by humans or machines.

Read more ›
Financial Times

Generative AI: hype not hyperintelligence is lifting values

Generative artificial intelligence could produce magic in the sky, says Sam Altman founder of pioneering start-up OpenAI. Successful entrepreneurs are entitled to make visionary statements.

Read more ›
Axios

Sara Fischer

Major websites are blocking AI crawlers from accessing their content

Nearly 20% of the top 1000 websites in the world are blocking crawler bots that gather web data for AI services, according to new data from Originality.AI, an AI content detector.

Read more ›
Nature

Andrea Taloni, Vincenzo Scorcia, and Giuseppe Giannaccare

Modern threats in academia: evaluating plagiarism and artificial intelligence detection scores of ChatGPT

Plagiarism and research integrity are sensitive issues in the academic setting, especially after the recent offspring of artificial intelligence (AI) and large language models (LLMs) such as GPT-4.0 [1].

Read more ›
Digiday

Sara Guaglione

Why publishers are questioning the effectiveness of blocking AI web crawlers

A number of publishers — including Bloomberg and The New York Times — were quick to block OpenAI’s web crawler from accessing their sites, to protect their content from getting scraped and used to feed the artificial intelligence tech company’s large language models (LLMs).

Read more ›

Frequently Asked Questions

Is the Originality.ai AI detector free?

Is Originality.ai free, or is there a free Originality trial? We don’t offer a free trial of Originality.ai. Instead, we offer a limited free AI detection tool, with 3 free daily scans.

What Can Cause False Positives?

Tools that use AI to rewrite or edit copy (e.g., some Grammarly features) can cause false positives. Shorter text may impact accuracy; we have a 100-word minimum at Originality.ai.

Classic Model: An AI detection score of 60% Likely Original and 40% Likely AI is not a false positive. It correctly predicted with 60% confidence that your content was Likely Original.

AI Allowance scans (new): Align how much AI you allow with project guidelines. 

How Can I Show My Work or Assignment is Original?

An AI score shouldn’t be used alone for academic integrity discipline.

Students and Writers: Share accuracy studies and show your writing process with our Chrome Extension.

Can I See Previous Scans?

Yes, scan history is stored for later retrieval or sharing. Complete removal of your account and data is available upon request.

What Languages Does Originality.ai AI Detection Support?

With Originality.ai, you can check if text is written by AI in 30 languages, with an overall accuracy of 97.8% for our multilingual model. Multilingual AI Accuracy Study.

Do Credits Expire?

Yes, per our Terms and Conditions, credits expire 2 years from the date of purchase.

How many free AI scans are there?

Check up to 2,000 words with the free AI checker, and run up to 3 free AI scans daily. To scan more words, upgrade to premium.

Do I need an account to run a free AI scan?

No, you can run up to 3 free AI scans daily without an account. To scan more words and run additional scans, you can conveniently sign up for Originality.ai.

Is my pasted text stored, shared, or used for training?

Text input into the free AI detector may be used for training. Users with an Originality.ai account can opt out of data use for AI training.

What does the AI score mean?

AI scores are predictions (probabilities) on whether text is AI-generated or Original (human-written). At Originality.ai, we emphasize that AI scores reflect probability, not guilt.
If you select AI Allowance, you choose how much AI you allow. So, your AI score reflects whether the percentage of AI writing is likely more or less than your selection.

Should an AI score be used on its own?

Use an AI score as one signal, not a final decision. Review other details like writing history and drafts before any high-consequence decisions. Always keep a human reviewer in the loop.

How does the Originality.ai AI detector work?

The Originality.ai AI Checker is based on a modified version of the BERT model and forms part of our patented all-in-one text analysis and verification system (U.S. Patent No. 12,253,988). For in-depth details on training, fine-tuning, and more, check out this blog post and this post to learn about our patented technology.

Does Originality.ai Detect AI Paraphrasing?

Originality.ai is accurate at detecting AI-paraphrased content (e.g., Quillbot). If you permit AI paraphrasing, adjust how much you allow with AI Allowance; read more in our accuracy study.

What Are AI Detection False Positives?

AI Detection false positives happen when human writing is incorrectly classified as AI-generated. At Originality.ai, we transparently share false positive rates in our accuracy study.

Note: False positive rates can vary by AI detection model and brand.