AI Text Detector
Check if a text shows AI-writing patterns.
How to use AI Text Detector
Paste the text you want to check — at least ~80 words gives meaningful results.
The analysis runs live: sentence rhythm, vocabulary variety, AI-typical phrases, repeated openings and human texture.
Read the verdict and each signal's explanation — not just a number.
Use it as one piece of evidence, never as proof on its own.
A free AI detector that shows its working
Search "ai detector free" and you get a row of tools that print a percentage and a verdict — and none of them can tell you why. This one takes the opposite approach. Paste a text and it measures the stylometric signals researchers actually use to tell machine prose from human prose, shows each one with its own score, and gives a verdict of Likely human-written, Mixed signals or Shows AI-typical patterns together with an AI-likeness score out of 100.
The point is not to replace your judgement but to inform it. If a student essay scores high, you can see whether that is because every sentence is the same length, because it leans on "delve", "furthermore" and "in conclusion", or because it never uses a contraction — and decide for yourself whether that is a language model or a nervous writer following a template.
The signals it measures
Burstiness is the strongest single signal: people write short sentences next to long ones, while language models tend to produce prose of remarkably even length. Vocabulary diversity is next — the ratio of distinct words to total words, which models keep suspiciously steady. Then a list of phrases that models over-use, repeated sentence openings, and the human texture that models under-produce: contractions, direct questions, asides, first-person detail.
Each signal is scored independently and labelled Human-like, Neutral or AI-like, so you can see which ones drove the verdict. A text with strong burstiness but a heavy load of model phrases is a different case from one that is uniformly flat — and the breakdown lets you tell them apart instead of hiding both behind one number.
- Sentence-length variation (burstiness)
- Vocabulary diversity (type-token ratio)
- Frequency of phrases language models over-use
- Repeated sentence openings and rhythms
- Human texture: contractions, questions, asides
What no detector can promise — read this before acting on a score
No AI detector, free or paid, is reliable enough to prove that a specific text was machine-written. That is not a limitation of this tool; it is the state of the art. Lightly edited AI output passes most checkers. Formal, well-structured human writing — academic English, legal prose, text by non-native speakers who learned from textbooks — gets flagged constantly. Short texts give almost no signal, which is why the box asks for at least 80 words.
Treat the result as one piece of evidence, never as a verdict on a person. If you are a teacher or editor, use the signal breakdown to start a conversation, not to end one. If you are a writer checking your own draft, the more useful reading is the opposite one: which patterns make your text sound generic, and what would make it sound like you.
Your text stays in the tab
Every step runs inside your browser, using the WebAssembly and Canvas APIs your device already ships with. No file is uploaded, no copy is kept, and nothing sits in a queue on a server waiting to be deleted — which is also why the tool keeps working with the network disconnected.
Most online AI checkers send your text to a server, and several keep it — some to train their own models. That is a poor trade when the text is an unpublished manuscript, a student's essay or a confidential report. The analysis here is pure statistics on the words you pasted, computed by JavaScript inside the page; nothing is submitted to any API and nothing is retained after you close the tab.
It is also why the tool is free without a word limit or a daily quota. Counting sentences and words costs nothing, so there is no premium tier, no sign-up wall and no reason to cap how many drafts you check.
Frequently Asked Questions
How accurate are AI detectors?
No AI detector — free or paid — is reliable enough to prove authorship. Edited AI output passes, and formal human writing gets flagged. That's why this tool shows the individual stylometric signals transparently instead of pretending certainty.
What signals does it analyze?
Sentence-length variation (humans are 'burstier'), vocabulary diversity, phrases that language models overuse (“delve into”, “furthermore”, “in conclusion”…), repeated sentence openings, and human texture like contractions, questions and asides.
Is the text I paste uploaded anywhere?
No. The analysis runs entirely in your browser — the text never leaves your device and is not stored.
Is this AI detector really free?
Yes — no sign-up, no word limit, no daily quota. The analysis is simple statistics computed in your browser, so there is nothing to charge for.
How accurate are AI detectors?
No AI detector — free or paid — is reliable enough to prove authorship. Edited AI output passes, and formal human writing gets flagged. That is why this tool shows the individual stylometric signals transparently instead of pretending certainty.
What signals does it analyse?
Sentence-length variation (humans are burstier), vocabulary diversity, phrases that language models over-use ("delve into", "furthermore", "in conclusion"…), repeated sentence openings, and human texture like contractions, questions and asides.
Is the text I paste uploaded anywhere?
No. The analysis runs entirely in your browser — the text never leaves your device and is not stored.
How much text do I need?
At least around 80 words for a meaningful reading; a few hundred is better. Very short texts do not contain enough sentences to measure rhythm or vocabulary, so the score is close to noise.
Can a human text be flagged as AI?
Yes, easily. Formal essays, technical writing and text by non-native speakers often show the same evenness a model produces. Use the signal breakdown to understand why, and never treat the score as proof.
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