Is this text written by a human or by an AI?
Paste any text (100-10,000 characters) and this tool returns a 0-100 score that says whether the writing looks machine-generated or human-written. We also show per-sentence highlights, so you can see which lines triggered the signal.
The check runs on our server in pure JavaScript, no ML model. We measure six things: burstiness (how varied sentence lengths are), average sentence length, AI cliche phrases like *"delve into"* or *"in conclusion"*, punctuation patterns like overused em-dashes, vocabulary entropy (how repetitive the word choice is), and formatting tells like bold inside bullet points.
Important: this is a hint, not a verdict. False positives are common, especially on technical writing, formal essays and translated text, which often look "AI-like" by these metrics. Never use it as evidence of cheating.
How to use it
- Paste the text in the box (a minimum of 100 characters, otherwise the statistics are not stable).
- Click "Analyze". The check runs on our server, the result comes back in well under a second.
- Read the headline score: 0-39 likely human, 40-64 mixed signals, 65-100 likely AI.
- Open the signals breakdown to see which heuristic fired. If only one signal flags, take the verdict with a grain of salt.
- Scan the highlighted text: red sentences are the ones that looked most AI-like, green ones the most human.
- Run it on a few paragraphs at once if you can, very short texts (one or two sentences) are almost impossible to judge.
When this is useful
Five honest scenarios. None of them treat the score as proof of anything:
- You wrote something and want a second opinion. Read the breakdown and the highlighted sentences. The signals that scream loudest (overused em-dashes, AI cliche phrases, uniform sentence length) are easy to edit out.
- You are reviewing copy submitted by a freelancer or contractor. A high score is a reason to ask follow-up questions, never a reason to accuse anyone of using AI without their input.
- **You are studying what *"AI prose"* actually looks like** and want a concrete tool to compare two paragraphs side by side: one you wrote, one you got from a chat assistant.
- You are editing AI-assisted writing and want a quick check whether the result still sounds like a person. Drop the rewritten version in, aim for under 40.
- You are a teacher running a classroom discussion about AI writing. The breakdown panel is a useful teaching aid, the score itself is a conversation starter, not a grade.
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