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Free AI Content Detector

Paste text to get an instant estimate of how "AI-written" it reads — based on sentence-length variety, word repetition and common AI phrasing. A useful guide, not a verdict (no detector is 100% accurate).

How this AI detector works

Rather than claiming a magic verdict, this tool looks at the signals that tend to differ between human and AI writing and combines them into an estimate: how often common AI-favored phrases appear, how much your sentence lengths vary ("burstiness" — humans vary more), your vocabulary richness, and average sentence length.

It runs entirely in your browser and gives you the underlying signals, not just a number — so you can see why a piece reads as more or less AI-like.

An honest word on AI detection

No AI detector is reliable — and that includes the paid ones. They produce false positives (flagging genuine human writing, especially from non-native speakers) and false negatives (missing AI text that has been lightly edited). Treat any detector’s output as a hint to review, never as evidence.

The better goal is not "undetectable" content — it is genuinely good content: accurate, original, helpful, and shaped by real expertise. That is what readers and search engines reward, however it was drafted.

Frequently asked questions

Can AI content be reliably detected?
No. Every detector, free or paid, has significant error rates in both directions. Lightly edited AI text often passes, and authentic human writing is frequently misflagged. Use detectors as a guide, not proof.
Will AI-written content get penalized by Google?
Google does not penalize content for being AI-assisted. Its guidance rewards helpful, original, accurate content regardless of how it was produced, and penalizes thin, spammy content however it was made.
What signals does this tool use?
AI-typical phrasing, sentence-length variety (burstiness), vocabulary richness, and average sentence length — combined into a single estimate with the raw signals shown.
Is it free and private?
Yes — free, no sign-up, and the analysis runs entirely in your browser.

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