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PassLab.

OUR TECHNOLOGY

The technology behind PassLab.

Most humanizers paraphrase everything and hope the score drops. PassLab works the other way round: find the sentences that carry the risk, rewrite only those, and check that nothing important moved.

EVERY PART OF A REWRITE

Four steps on every draft.

  • 1. Estimate risk sentence by sentence

    Each sentence gets an AI risk estimate, so the draft is mapped into high, uncertain and low-risk passages before anything is rewritten.

  • 2. Rewrite only what needs it

    With Smart coverage, low-risk sentences are left word for word. A full-draft pass is there when the whole text needs work.

  • 3. Check the details

    Names, numbers, quotes and citations are checked against your original during the rewrite, so the facts your argument depends on survive.

  • 4. Keep the better version

    The rewrite is compared with your original. If it would make the draft worse, PassLab keeps your original and says so.

DETECTOR ESTIMATES

Twelve views of the same draft.

Detectors disagree. PassLab estimates how a draft is likely to read to twelve of them, so you can see where the risk is and which detectors you care about.

  • Separate estimates per detector

    Turnitin, GPTZero (beta), Originality.ai, Copyleaks, Pangram, Winston AI, ZeroGPT, Sapling, QuillBot, Grammarly and two StealthWriter versions.

  • Your priorities steer the rewrite

    Choose up to three detectors. The rewrite focuses on them while PassLab keeps checking the rest.

  • Estimates, clearly labelled

    Every score is PassLab's own estimate, not an official detector result. Scores describe writing patterns, not proof of authorship.

WHAT YOU SEE

Nothing changes behind your back.

Every result shows the rewritten text, your original and a Changes view that highlights each sentence PassLab touched. The AI risk forecast shows the estimate before and after, and the sentence map lists the passages that still carry risk, so you can run another pass on just those.

Results and their originals are saved to My drafts. You can copy or download the version you choose, or come back later and continue from where you left off.

WHAT WE DO NOT CLAIM

Honest about the limits.

No tool can promise a detector outcome. Detectors change, their thresholds differ, and official results can differ from any estimate. PassLab is built to lower AI risk while keeping your meaning, and to show you exactly what it did, so you stay in charge of the final draft.

PassLab is not affiliated with any detector listed on this site.

See it on your own draft.

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