linxiaotao/fuckclaude

FuckClaude is a small bilingual website, in English and Chinese, that scans your web browser to estimate whether Claude Code would classify you as a China based user. The project explains that when Claude Code is pointed at a non official server address, it was reported to read the computer's system timezone and network proxy hostname, then hide that result inside the date line of its own system prompt using subtle character substitutions. Since a web page cannot see everything a desktop program can, this tool instead checks whatever signals a browser is able to observe and estimates how similar they look to a typical China based setup. The page runs a short animated scan and shows a gauge that rises as more matching signals are found, then gives a final verdict along with the list of signals that triggered it. The project states that everything runs entirely inside your browser and that no data is sent anywhere. The signals checked include the system timezone, browser language, whether certain Chinese fonts are installed, the type of browser or in app browser being used, hints about the device brand, and how the browser formats dates, numbers, and emoji. Each signal is given a different weight based on how reliable it is, and the site explains the exact weighting used to reach a final score out of one hundred, divided into low, medium, and high risk bands. Beyond the browser page, the project also offers a small server side endpoint that can be queried from the command line using curl, which estimates the same kind of score based on network request headers like language and approximate location instead of full browser signals. The project is built with the Astro web framework, output as a static site with one small serverless function for the command line endpoint, and uses the pnpm package manager. The README also lists several paid third party services as sponsors, mostly related to accessing AI tools or masking browser fingerprints, though the core scanning tool itself does not depend on any of them to function.