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AI Detector
Paste a passage and see how much of it reads as machine-written, sentence by sentence, with an honest account of how much that number is worth.
AI detector
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What the number actually means
The score is a probability, not a verdict. It says how closely the writing matches patterns common in machine-generated text: even sentence lengths, predictable word choices, an absence of the small irregularities people produce without noticing.
That is why the sentence-level view matters more than the headline figure. A passage at 60% is usually not 60% machine-written — it is more often two or three flat sentences pulling the average up, and those are the ones worth rewriting in your own voice.
Detectors get it wrong, in both directions
Formal academic prose is the writing style detectors most often misread. Careful structure, controlled sentence length, and restrained vocabulary are exactly what these systems learned to associate with generated text — so a well-drilled student essay can score high while nothing about it is dishonest.
They also miss things. Machine text that has been edited by a person frequently reads as human, because it now is, partly. Treat a result as one signal among several. Anyone who tells you a detector is definitive is selling something.
Hidden characters are the real risk
The checker looks for zero-width characters and lookalike letters borrowed from other alphabets. These are invisible on screen and get inserted to break detectors.
If your text contains them, that matters far more than any score. Submitting work with deliberate obfuscation in it is treated as intent, and intent is what turns a conversation about a grade into a misconduct hearing. If they are flagged here, strip them before you do anything else.
What to do with a high score
Read the sentences it flagged. Where a line states something obvious in a neutral register, replace it with the specific version: name the study, give the figure, say what you actually think follows from it. Detail is what generated prose is usually missing, and it is what markers reward anyway.
If the whole piece reads flat, rewriting sentence by sentence will not fix it. That is a structure problem wearing a style problem's clothes.
Related tools and guides
- Plagiarism checker The other question markers ask
- Paraphrasing tool Rewriting the flat sentences
- Thesis statements When the problem is the argument
- Editing and proofreading A human read before submission
Frequently asked questions
Is this AI detector free?
Yes, up to 1,000 words per check with no account. Longer pieces should be checked a section at a time.
How accurate is AI detection?
No detector is reliable enough to be treated as proof. They are trained on patterns, and careful academic writing shares many of those patterns, so honest work is flagged regularly. Use the result as a prompt to reread, not as a verdict.
Why did my own writing get a high score?
Because it is probably well organised and evenly written. Consistent sentence length and neutral vocabulary are the signals these systems weigh most heavily, and they cannot tell discipline from generation.
Can I use this to make text pass a detector?
That is not what it is for, and we will not claim it works. Detectors are updated constantly and disagree with each other, so nobody can promise a result that will hold.
What are zero-width characters?
Invisible characters inserted between letters to disrupt detection. They do not show on screen but they are trivially found, and submitted work containing them is treated as deliberate deception rather than a borderline case.
Is my text stored?
The passage is sent to be analysed and is not kept afterwards. This check cannot run in your browser, unlike most of the tools on this site.