Free AI detector for ChatGPT, Claude & Gemini

Paste your text to get an overall AI score and see which sentences read as AI-written, each with its own likelihood — not just one number.

PlagiarismAI detector
0 / 1,000 words·0 chars
Scan options
What you get
  • Trained on every major AI model
  • Sentence-by-sentence AI-generation report
  • Auto-detects your language
  • No signup needed for your first scan
  • First check free, no sign-up
  • Sentence-level AI likelihood
  • Never used to train AI

Check for AI wherever you write

Web app

Paste or upload a file and get the AI report, saved to your history.

Open the app

Chrome extension

Check any text box or selection on the web from Chrome’s side panel.

Chrome extension

Google Docs add-on

Check the whole document for AI writing without leaving Google Docs.

Docs add-on

API

Send text from your own app and get per-sentence AI results as JSON.

API docs
The AI report

See which sentences read as AI-written

An overall AI score, a likelihood for every sentence, and the tools to review, share and rescan — in one report.

Highlighted sentence by sentence

See exactly which sentences read as AI-written — not just one number for the whole text.

Essay with AI-likely sentences highlighted one by one
Confidence you can read

An overall score plus a High to Low confidence scale.

AI score of 44% with a High, Medium-high, Medium and Low confidence legend
A likelihood for every sentence

Step through flagged sentences one by one, most likely first.

List of nine sentences, each with its own AI likelihood from 70% to 100%
Leave remarks

Add feedback on any sentence, reply, and resolve.

A remark on a highlighted sentence, with Resolve and Reply
Organised in folders

Keep every check filed by class or project.

Folders: All reports, History essays and Research papers
Share, export and rescan

Send a secure link, download a PDF, or edit and rescan in the same window.

Report toolbar: Find, text size, Display, Review and Edit, Share, PDF and Rescan
Sentence-level confidence

A likelihood for every sentence, not one verdict

The AI checker highlights each sentence that reads as machine-written and shows how confident it is. You can tell a single flagged line from a paragraph that is AI-written throughout.

  • Overall AI score for the whole text
  • High to Low confidence on each sentence
  • A likelihood to review, not proof
AI detection report: flagged sentences highlighted in the text, a 50% AI score, and numbered notes pointing to the per-sentence probability and the overall score
Plagiarism + AI

Plagiarism and AI in one report

AI-written text is usually original, so a plagiarism check alone won’t catch it. Run both on the same text and see copied passages and AI writing side by side.

  • Matched sources underlined by colour
  • AI-likely sentences in the same view
  • One upload, one shareable report
Plagiarism report: matched passages underlined in the colour of their source, an 82% score and each source with its link

Detects text from every major AI model

Trained on output from the leading language models and retrained as new ones ship, including lightly edited and paraphrased AI text.

  • ChatGPT (GPT-4o, GPT-5)
  • Claude
  • Gemini
  • Copilot
  • Llama
  • Mistral
How it works

Check any text for AI in three steps

  1. Paste or upload

    Paste text or upload a Word, PDF or text file. Your first AI check needs no account.

  2. We score each sentence

    Every sentence gets an AI likelihood, and the whole text gets an overall AI score.

  3. Review and decide

    Read the highlighted sentences in context, rewrite or discuss them, then rescan.

Watch the 2-minute tour: AI detection and plagiarism checking in one report, plus citations, Chrome and Google Docs.
FAQ

AI detector questions

Yes. Your first AI check is free without an account, up to 1,000 words, with the full AI score and sentence-level highlights. A free account gives you 3,000 words every month. Paid plans add longer documents, bulk upload, folders and API access.

Check your text for AI, free

Your first AI check needs no account, up to 1,000 words.

Check your writing where you write it