README.md

metadata

title: Free AI Detector
emoji: 🔍
colorFrom: blue
colorTo: purple
sdk: static
pinned: true
license: mit
short_description: Free, no-signup AI detector with sentence-level analysis.
tags:
  - ai-detector
  - free-ai-detector
  - gptzero-alternative
  - turnitin
  - content-authenticity
  - chatgpt-detector
  - gpt-detector
  - ai-checker
  - detect-ai-text
  - ai-plagiarism-checker
  - multilingual

🔍 Free AI Detector

Paste any text and see, sentence by sentence, whether it was written by AI, edited by AI, or written by a human. Free forever, no sign-up, 100% private.

Official Lynote page on Hugging Face. Detects output from ChatGPT, GPT-4/GPT-4o, Claude, Gemini, DeepSeek, Llama and other LLMs, in English and Chinese.

Open source — this detector's source code is on GitHub: github.com/lynote-ai/ai-text-detector

The problem

AI-generated text is flooding classrooms, publications, hiring pipelines and content platforms — and it is getting harder to tell apart by reading alone. A free, transparent check helps educators, editors, hiring teams and curious readers verify authorship without paying for a subscription or creating an account.

How to use

1. Copy the text you want to check (80–5,000 characters).
2. Paste it into the box and hit analyze.
3. Get an overall AI score plus sentence-level highlights showing exactly which parts read like AI output — including mixed human/AI text.

Try the full product with per-model scores and batch analysis: lynote.ai/ai-detector

Methodology

The detector is transparent, dependency-light and runs on CPU only — no model download, starts instantly:

• Sentence-rhythm uniformity (burstiness) — humans vary sentence length a lot; LLMs tend to settle into a uniform rhythm.
• Formulaic phrase density — known AI clichés ("it is important to note that", "delve into", "值得注意的是", "综上所述") are counted.
• Repeated n-grams & repeated sentence starters — statistical ties in word choices that LLMs over-produce.
• Vocabulary uniformity — the ratio of unique words to total words.

These signals are combined into a single probabilistic score, computed per sentence and over the whole text. The same methodology powers the Free AI Humanizer's target phrasing lists, so the two tools are consistent by design.

Limitations (read this before judging anyone)

• A score is a probabilistic signal, not proof of authorship.
• No detector is perfect. False positives are possible, especially with short, formal, technical or highly structured writing.
• Very short, translated, or heavily edited texts are easy to misjudge.
• Do not use this demo alone for disciplinary, legal, or moderation decisions.

More free Lynote tools

• ✍️ Free AI Humanizer — rewrite AI text into natural human prose
• 🖼️ Free AI Image Detector — check if an image was AI-generated
• 🧠 humanize-text-model — MIT-licensed bilingual T5 model behind the humanizer

Privacy

The app processes text in memory and does not intentionally store submitted drafts. Hugging Face infrastructure and platform logs remain subject to Hugging Face policies.

License

MIT. See the linked repositories for their respective source and license notices.