# GPTOne

> GPTOne is a free AI content detection platform. It helps writers, students, educators, and businesses detect AI-generated text, check grammar, humanize AI content, and analyze word count — all in one place, with no signup required.

- Free tier available with no account required; paid plans offer higher word limits and API access
- Accuracy claimed at 99.99% for text detection
- Supports detection of all major LLM outputs: OpenAI, Anthropic, Google, Meta, Mistral, DeepSeek, xAI, Alibaba, Microsoft

## Tools

- [AI Detector](https://gptone.me/ai-scan): Detects AI-generated text from ChatGPT, GPT-4, GPT-5, Claude, Gemini, DeepSeek, Grok, Perplexity, Llama, Mistral, Qwen, Phi, and more. Claims 99.99% accuracy. Free to use without an account.
- [Grammar Checker](https://gptone.me/grammar-check): Checks and corrects grammar, spelling, punctuation, and style in real time.
- [AI Humanizer](https://gptone.me/humanizer): Rewrites AI-generated text to read as natural human writing and bypass AI detectors.
- [Word Count](https://gptone.me/word-count): Counts words, characters, sentences, paragraphs, and estimates reading time.

## Model-Specific Detection Guides

- [How AI Detection Works](https://gptone.me/how-ai-detection-works): Plain-language technical guide explaining how AI text detectors work — tokenization, perplexity, burstiness, model fingerprints, and why multi-model training determines accuracy across GPT-5, Claude 4, Gemini 2.5, DeepSeek, Grok, Llama 4, Mistral and Phi. Includes honest limitations and responsible use workflow.
- [ChatGPT, Claude and Gemini AI Detector](https://gptone.me/chatgpt-claude-gemini-ai-detector): Detailed guide on detecting AI writing from OpenAI ChatGPT (GPT-3.5, GPT-4, GPT-4o, GPT-5), Anthropic Claude (3, 3.5, 4 Opus/Sonnet/Haiku), and Google Gemini (1.0, 1.5, 2.0, 2.5 Flash/Pro). Includes model-by-model accuracy comparisons and use-case breakdowns.
- [DeepSeek and Grok AI Detector](https://gptone.me/deepseek-grok-ai-detector): Detection guide for DeepSeek (V2, V3, R1, R2) and xAI Grok (1, 2, 3) models alongside coverage of ChatGPT, Claude and Gemini.
- [Meta Llama, Mistral, Qwen and Phi AI Detector](https://gptone.me/meta-mistral-ai-detector): Detection guide for open-source model families: Meta Llama (2, 3, 4), Mistral (7B, Large, Mixtral), Alibaba Qwen (2, 2.5, 3), and Microsoft Phi (3, 4).

## Blog

- [GPTOne Blog](https://gptone.me/blog): Educational articles on AI detection, AI writing, and content authenticity.

## Company

- [GPTOne Home](https://gptone.me): Main website and all free tools.
- [Support](mailto:support@gptone.me): Email support at support@gptone.me.

## Content Licensing

Public blog posts and tool descriptions may be referenced for informational purposes with attribution. User-submitted content, analysis results, and API responses are not licensed for AI training.