ZeroClaude
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Free AI detector for theses and papers

Paste a chapter or upload a .docx or .pdf, and see which sentences read like AI before your school runs its own check.

0/15,000 Characters

Why check your thesis before you submit

Sentence by sentence

Every sentence that reads like AI is highlighted, so you know exactly what to revise.

Built to avoid false alarms

Thresholds are set on human writing, separately for Chinese and English, to keep false positives low.

Upload whole chapters

Upload .docx, .pdf or .txt files instead of copying and pasting.

Your text is not stored

We keep scores only, never your text, so your unpublished thesis stays yours.

How this relates to your school's check

Many universities now set a maximum share of AI-generated content for theses, often between 15% and 40%, and check it with their own systems. Different systems use different models, so the same text can get different scores. ZeroClaude is an independent self-check: use it to find passages that read like AI and rewrite them in your own words. It is not affiliated with any school or checking service, and its result is not an official report.

Tips: check one chapter at a time, because longer passages give more reliable scores; rewrite flagged sentences in your own words rather than swapping synonyms; and keep your drafts and notes as evidence of your own work.

FAQ

Your questions, answered

Is it free?
Yes. You can check up to 15,000 characters at a time without an account. Paid plans raise the limit and add PDF reports and batch upload.
Will my result match my school's system?
Not necessarily. Each system uses its own model and thresholds, and the same text can score very differently across them. Use ZeroClaude as an early warning: find the passages that read like AI and rewrite them yourself before the official check.
Which languages does it work in?
Detection is trained and calibrated for English and Chinese. Text in other languages can be checked, but the result is marked as experimental until we have checked that language for false positives.
Do you keep my text?
No. Your text is only used to produce the result and is never written to a database. If you are logged in, your history keeps the score and date, not the text.
My own writing was flagged. What should I do?
Formal academic writing can look AI-like, especially abstracts and literature reviews. Rewrite flagged sentences in your own voice, add specifics from your own research, and keep your drafts and notes as a record of your work.
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