AI detector with sentence-by-sentence results

See which parts of a text read as AI-generated, not just a single number. Every sentence gets its own likelihood, highlighted in place, with the patterns behind the score explained.

Try the AI Detector freeSee plans

Free plan available. No card required.

Why use the TextLumi AI Detector

Sentence-level highlighting

Each sentence is scored and colour-coded, so you can see exactly where the AI-like patterns are.

Explained, not just scored

A short summary lists the signals found, such as uniform rhythm or stock phrases, and the signs of human writing.

Calibrated to avoid false alarms

Formal, academic and non-native English isn't treated as evidence of AI on its own, and short texts get cautious scores.

Fix what it finds

Send flagged text to the AI humanizer in one click, then check it again.

How to use it

  1. 01

    Paste the text you want to check (longer passages give more reliable results).

  2. 02

    Read the overall likelihood and the highlighted sentences.

  3. 03

    Revise or humanize the flagged parts and check again.

AI Detector FAQs

How accurate is an AI detector?

Every AI detector is probabilistic and can produce false positives and false negatives, ours included. Treat the score as one signal alongside your own judgement, never as proof.

Can it tell if ChatGPT wrote something?

It estimates how strongly the writing shows patterns typical of AI models such as ChatGPT. It can't prove who wrote a text.

Should teachers use it to judge students?

Not on its own. A score is not evidence of misconduct. Use it to start a conversation, not to decide an outcome.

Is the AI checker free?

Free accounts include a few checks a month. Paid plans include more checks and longer documents.

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