Free Tool

AI Checker

Paste a section of your draft. This tool measures 13 stylistic signals that AI-generated text tends to show, adapted from published detection research, so you know what a supervisor or reviewer might notice before you submit.

Runs entirely in your browser. Your text is never uploaded, never stored, never seen by us.

Read this first. No tool can prove whether a text was written by AI, including the commercial ones. This checker reports stylistic signals only. Formal academic writing by non-native English speakers is often wrongly flagged by AI detectors; treat every result, here and anywhere else, as a prompt to review your writing, never as a verdict.

0 words (minimum 150)

How This Works

The Explanatory Machine Architecture Detection Framework

Every number above comes from a measurement you can check yourself. Here is what each one does.

Sentence Length Burstiness

Human writing alternates long and short sentences without planning to. Generative models hold sentence length close to a mean. Reported as a coefficient of variation: the lower the number, the more even the rhythm. A paragraph of sentences running 32, 24, 6, 17 and 27 words scores well. One running 21, 22, 20, 23 and 21 does not.

Clausal Punctuation Uniformity

Measured as the entropy of punctuation marks across the text. Human writers reach unevenly for colons, question marks, dashes and parentheses. Generated prose settles into commas and full stops, which lowers the entropy.

Vocabulary Diversity

A moving window across the text measures how much of the vocabulary is fresh. Human writers vary: dense passages, then plainer ones. Models hold lexical variety unusually steady from first line to last.

Algorithmic Signature Markers

A lexicon of stock phrases and constructions that appear far more often in generated prose than in human drafts: "delve", "crucial", "moreover", "serves as a", "not only X but Y", trailing "-ing" clauses, and the rhythm of three. Counted per 1,000 words so length does not distort the figure.

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