Originality.ai℠ is the Most Accurate AI Detector in third-party studies. Check up to 2,000 words with 3 Free AI Scans Per Day.

















































Step 1
Add Text
Paste, Upload, or URL

Step 2
Scan
AI Allowance, Plagiarism, Content Quality, and more

Detect AI Paraphrasing
Our team actively tests AI tools that change, modify, or edit text (e.g. Quillbot or Grammarly) and continuously improves our AI detector to ensure attempts to hide AI-altered text are still detectable.

Manage False Positives
Check for AI and plagiarism with the Originality.ai Chrome Extension.
Peace of mind for writers and students to show the authorship of writing, with a Writing Replay.


Writers, Editors & Marketers

Teachers & Students

Enterprise & Schools
Discover flexible pricing for students, teachers, small teams, agencies, publishers, and enterprise.

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.
Our AI Detector, available to try below, has been shown by multiple independent studies to be the most accurate AI Detector they tested. It is accurate on GPT-5, ChatGPT, Claude, Gemini, Grok and all other Popular AI writing tool text.
Try the AI Detector for free above. Free scans are limited. For higher word count limits, saved reports, plagiarism checking, readability, grammar, fact checking, team tools, and API access, sign up for the full version.
Use AI detection 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.
Trusted by Industry Leaders


























A Complete Content Integrity Suite
AI Detector By Originality.ai™ offers a complete suite of patented AI tools for writers, students, editors, marketers, web publishers, and educators including, AI detection, Plagiarism Checking, Fact Checking & Grammar Checking.
Deep Scan ›
See why text is likely flagged as AI + how to ethically edit it, so your work is more likely identified as original!
AI Checker ›
Accurate AI Detector in peer reviewed studies. Try our free AI Checker above.
Plagiarism Checker ›
See if text has been plagiarized from anywhere on the internet.
Content Quality Score ›
Confidently check if content is low, good, or high quality before you click submit.
Readability Checker ›
Optimize readability for your target audience to communicate clearly.
Bulk Scan ›
Scale content QA and scan an entire website’s content easily.
AI Allowance ›
Now in Beta: Flexibly adjust the AI% that you permit for each scan.
Fact Checker ›
Use our fact checking aid to help ensure your content is factually correct.

Step 1
Paste or Upload Text
Login to Originality.ai and paste, upload, or enter a URL to input text into the editor.

Step 2
Select Scan Types
Choose which type of scan you’d like to run, AI Allowance, Plagiarism, Content Quality, Grammar and more!

Step 3
Click Scan
Click ‘Scan’ to get scores for each scan type. Was your text flagged as Likely AI? Run Deep Scan for tips.
In internal testing and 3rd party peer-reviewed studies, the Originality.ai AI detector, has repeatedly been found the most accurate at detecting AI content.
Originality.ai is built to detect AI text from leading LLMs: including GPT-5.5, GPT-5, Claude Opus 4.7, Claude Opus 4.8, Claude Fable 5, Gemini 3, Gemini 3.1 Pro, Gemini 3 Flash, Gemini 3.5 Flash, Grok 4.1 Fast, Grok 4.3, DeepSeek V3.2, V4 Flash, and V4 Pro and other popular AI writing tools.
Any AI detector accuracy claim that is not transparently supported by methodology, benchmark data, and independent or reproducible analysis should be viewed skeptically.
Study
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

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.

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.

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.

Writers, Editors & Marketers

Teachers & Students

Agencies & Enterprise
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.