Switch to Check Risk for the score and the sentences behind it. Free, no sign-up, and the check runs in this tab.
Whoever reads your work next may run it through a checker you cannot see the output of. This is the rehearsal: paste the draft, find out which sentences that kind of tool keys on, and decide what to do while you still have the choice. The checker runs in this tab, and your draft is never sent to a detector.
Most confusion about AI checkers comes from collapsing three separate tools into one word. They make different claims and only one of them can show you its evidence.
Estimates the probability that a language model produced the words. It compares your text against statistical habits, not against any archive. There is no source document it can point to, because there is no source document. The answer is always an inference.
Matches your text against a corpus of existing documents and shows you the overlap. When it flags something it can name the source and quote the line. That is a different kind of claim, and a far more checkable one.
Neither. It reports which specific constructions in your draft are the ones AI checkers key on, and shows you the sentences that contain them. It is a rehearsal for the check you cannot run yourself.
41 surface patterns plus 3 whole-document cadence detectors, all executing in your browser. How the score is composed →
Straight into the box at the top of this page. No account, no upload, no word cap. Scoring starts once there are 25 words, because a rate computed over two sentences means nothing.
Low, Moderate, Elevated or High. The number moves as you type and the exact value matters far less than which band you are sitting in and which paragraph put you there.
Every finding underlines the characters that triggered it and explains itself in a sentence. The registry ships 44 of them, so the report usually tells you something specific about your habits.
If the draft is machine-flat, rewrite it. If you wrote it yourself and the reading is still high, do not sand your voice down — export a signed evidence report instead and keep the receipt.
Statistical checkers flag whatever sits furthest from the writing they were trained on. In practice that means they flag people, and not at random.
Checkers do not fail evenly. Peer-reviewed work found 61% of TOEFL essays by non-native English speakers falsely flagged across seven commercial detectors, while essays by native speakers came through nearly clean. Who gets flagged, and why it happens covers the study, the mechanism and the four cohorts in full.
A planned audit of commercial detectors against cohort-labelled human writing. When it runs, the methodology and the corpora will be published and every run downloadable as CSV, across 4 cohorts. Cohort-level false-positive rates are the number this category does not report, and that is the number the audit is built to produce.
A percentage from any AI checker is a classifier's confidence, produced from writing style alone. It is not testimony, it carries no chain of custody, and the threshold that turned your draft red is not published anywhere.
What can be shown is the drafting itself. Write in the editor and it records your local edit history and cadence, then seals the record with a signing key your browser generates and keeps. The verifier checks that signature in the reader's own browser, no account required.
The checker is 41 pattern rules and 3 document statistics running as JavaScript in this tab. No model, no request, no account. Your draft is never submitted to a detector.
The score is computed in this tab, over a string that stays in this tab. There is no analysis endpoint behind it.
Your text is not passed to GPTZero, Turnitin, Copyleaks or any other classifier. That holds for every feature on this site.
Load the page once and disconnect. The checker keeps scoring, because the rules are already here.
Do not chase a number. Fix the writing that produced it. The humanizer takes the same highlighted clauses and rewrites them inside your own measured style, one at a time, with you approving each change.
You get the exact location of every stock opener, negation pivot and flat-rhythm run in the draft, so the sentences you keep are the ones you decided to keep. What a named detector will output on a given day is not something any tool can tell you.
No account and no limit. The checker runs in your browser, so there is no server cost per check and nothing to meter. Rewriting and evidence reports live in the full editor.
No. A plagiarism checker matches your text against documents that exist and can quote the source it matched. An AI checker estimates a probability from writing style and has no source to show you. The two get discussed as one thing and they are not remotely the same kind of claim.
Not necessarily. Turnitin, GPTZero, Copyleaks and the rest run their own classifiers on thresholds they do not publish. This tool shows you which features in your draft that class of system keys on, sentence by sentence, which is the part you can act on.
Most institutional policies say no, but most AI checkers cannot tell. Grammar assistance and speech-to-text both flatten sentence rhythm, which is one of the properties detectors measure. That is a large part of why assistive-technology users show up in false-positive research.
Yes, for any text you have the right to read. The checker runs in your browser, so the text stays in the tab.
Checking your own draft is not usually restricted. Where generative AI is not permitted in submitted work, that rule governs regardless of which tool you use.
Free AI checker. No account. Runs in your browser.