VerifyAI

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AI text detector

Upload an essay, report, statement or PDF and find out whether a person or an AI model wrote it — with the sentences that gave it away highlighted.

Drop your files here, or click to choose

PDF, TXT or Markdown · up to 8 MB each · up to 10 at once · 5 free checks per hour

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What this checker looks at

Sentence-level highlighting

The review quotes the exact sentences that read as machine-written, and we mark them in your original text so you can see why.

Style and rhythm analysis

AI writing favours even sentence lengths, stock transitions and hedged, generic claims. Human writing is lumpier and more specific.

Document metadata

For PDFs we read the producer, creation tool and timestamps, which often reveal an export straight from a chat tool or template.

Model attribution

When the style matches a known model closely, we name the closest match — ChatGPT, Claude, Gemini and others — as a best guess, not proof.

How to use it

  1. 1

    Drop a PDF, TXT or Markdown file onto the box above, up to 8 MB on the free check.

  2. 2

    The file is fingerprinted with SHA-256 and read by the AI review, which flags passages that look machine-written.

  3. 3

    Read the verdict, the score and the highlighted sentences before you grade, publish or accept the document.

  4. 4

    For saved history and a certificate you can share, create a free workspace and upload the file there.

Questions

Often, yes. Text from ChatGPT, Claude and Gemini has recognisable rhythm and phrasing. We show the flagged sentences so you can judge the evidence yourself.

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