Unfox AI

Unfox AI is a free, browser-based AI content detector that helps you determine whether a piece of text was likely written by a human or generated by an AI model like ChatGPT, Claude, Gemini, or DeepSeek. It's built for students, educators, writers, editors, SEO teams, and businesses that need a quick, reliable way to scan essays, articles, reports, or marketing copy for AI traces without the cost or complexity of paid tools. Unlike many detectors that give you a single overall percentage, Unfox breaks down the text sentence-by-sentence, highlighting which sections carry stronger AI signals, so you know exactly where to focus your review. The tool analyzes linguistic and statistical patterns—such as predictability and sentence variation—rather than looking for copied phrases. It supports 17 mainstream languages, including English, Chinese, Japanese, German, French, Spanish, Korean, and more, and automatically detects the input language for accurate results. That makes it a practical choice for multilingual teams and international content workflows. Unfox is privacy-first: your content is not stored after detection. There's no sign-up required, and every feature—including batch detection and API access—is free. You can paste text directly, upload documents, or use the provided sample text to test how it works. The detection report gives you a reference confidence score, an overall AI percentage, and a visual breakdown of sentence-level signals. The homepage stresses that AI detection results are probability-based signals, not proof of authorship. That's a refreshingly honest stance—false positives are possible, especially with academic or technical writing. Unfox positions itself as a practical, accessible alternative to paid services like Originality.ai or GPTZero, with the added benefit of being completely free and supporting a wider range of languages out of the box.