Instant originality check

Spot AI-like writing
in seconds — no login.

This is a browser estimate. It does not search other papers and it does not prove authorship. About 60 words is the useful minimum. Nothing is uploaded.

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The free check needs no login. The text stays in the browser.
Live preview62% AI-like
62%AI-LIKE

Likely AI-assisted

Stock phrasing + low burstiness pulled the score up. Confidence 71%.

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Furthermore, a robust framework for data collection is essential. Moreover, researchers must delve into the multifaceted nature…

Burstiness
Phrasing
Surprisal
Strict mode · higher sensitivity
9 signals · one calibrated score
No login requiredClient-side — text never leaves your deviceLaTeX stripped before scoring~60+ words for a usable estimate
How it works

Paste text. Get a score. Improve the draft.

Paste text. Read the score. The free check needs no account and does not upload the passage.

01

Paste anything

Plain prose or LaTeX. Math, commands, and verbatim blocks are stripped so only the writing is scored.

02

Nine-signal ensemble

Surprisal, burstiness, lexical diversity, n-grams, function words, openers, punctuation, stock phrases, and contractions.

03

See what flagged

Gauge + per-signal bars + sentence heatmap. Hover any sentence for its local AI-like score.

What we measure

Signals that separate generic AI cadence from human rhythm.

Perplexity proxy
Surprisal from word frequency

Low, flat surprisal across tokens often reads as AI. We use a bundled Zipf frequency model — a proxy, not a full language model.

Rhythm
Burstiness & punctuation

Humans vary sentence length; many models don’t. Uniform commas and sparse questions or dashes also nudge the score.

Lexicon
Stock AI phrases & openers

“It is important to note,” “delve into,” “multifaceted,” repeated transition openers — classic tells we weight explicitly.

Stylometry
Function words, MATTR, contractions

Grammar-word share, moving-average type-token ratio, and contraction rate help catch formal, over-smoothed prose.

Be careful

A useful estimate — not a verdict.

Formal human academic writing can score high. Lightly edited AI can score low. No detector, including paid ones, can prove authorship. Use this to revise your own writing. Do not use it to accuse someone.

Check a passage, then keep the draft.

Paste about 60 words for a usable estimate. The free check needs no login and uploads nothing. Sign up to open the same draft in the editor.

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The score is an estimate, not proof of authorship.
Questions

What the score is, and what it is not.

What does this detector do?

It estimates how AI-like a pasted passage reads. The check runs in the browser. The text is not uploaded.

Is this a plagiarism checker?

No. It does not search published papers. Use the plagiarism detector for source overlap.

Can it prove someone used AI?

No. Formal human writing can score high, and edited AI can score low.

Check this draft in the editor

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