AI Detector
See which sentences read like AI-generated writing, how strongly, and why. Results are an estimate, not proof of who wrote a text.
What the AI Detector measures
The AI Detector splits your text into sentences and estimates, for each one, how likely it is to read like text produced by an AI writing tool. It looks at the kind of patterns such tools tend to produce: stock phrases, evenly sized sentences, formulaic transitions and claims that sound confident but say little.
The headline number is the share of your text that sits in sentences scored at 50% or higher. It is a summary of the sentence scores, not a separate verdict, so the highlighted sentences show you exactly where it comes from.
How to read the results
Start with the highlights
Sentences scored 75% or higher get a strong highlight and those from 50% to 75% a light one. Sentences without a highlight scored under 50%.
Open a sentence
Select any sentence to see its score. "Why?" lists the patterns that may make it read as AI-like, with a short explanation.
Revise, then check again
Rework a sentence yourself or with "Rewrite this sentence". A rewrite never changes the score on screen; run a new check to score the revised text.
Limits of AI detection
AI detection is probabilistic. No detector, including this one, can tell for certain who or what wrote a text. Careful human writing can look formulaic, and edited AI output can look human. Short texts, lists, technical writing and writing by people working in a second language are especially easy to misread.
Don't use a result as proof that someone did or didn't use AI, and don't use it on its own to make decisions about grades, jobs or accusations. While the engine is labelled Beta, its results are indicative only and may change as it improves.
Frequently asked questions
Is the AI Detector free?
Yes, you can try it without an account. Guests get 3 runs a day of up to 1,000 words each. Signing in with your email gives you more free checks every day. See Pricing for the current limits.
Can this prove that a text was written by AI?
No. The result is an estimate based on writing patterns, and every detector makes mistakes in both directions. Treat it as a reason to look more closely, never as evidence on its own.
How much text do I need?
At least 30 words. Very short texts don't give the detector enough to work with, so a few sentences of real writing give a more useful result than a single line.
Does rewriting a sentence lower the score?
Not on screen. A rewrite gives you an alternative sentence, but the score you see belongs to the text you checked. Paste your revised text and run a new check to score it. Sentence rewrites use your rewrite allowance, the same one the AI Humanizer and AI Paraphraser use.
Do you keep my text?
Your checks are saved in your history so you can reopen them, and you can delete any entry at any time from the History panel. Our Privacy Policy explains what we store and for how long.