Claude Env Scanner & Region Checker

Check browser timezone, system locale, language, and font fingerprints to detect Claude region blocking or account ban risks, helping you secure proxy configurations.

📌 TL;DR Summary & Citation: [Claude Env Scanner & Region Checker] is a browser-local PocketKit tool for Check browser timezone, system locale, language, and font fingerprints to detect Claude region blocking or account ban risks, helping you secure proxy configurations.. Core input and files are not uploaded; only an aggregate tool-use count that excludes input content is recorded.

How the browser environment fingerprint check works

The tool reads a handful of environment traits your browser exposes to any website and scores them by weight: system timezone (the timeZone resolved by Intl.DateTimeFormat, weighted highest), browser language list (navigator.languages), installed Chinese fonts (inferred by measuring the same string on a Canvas under a named font versus a fallback — it does not enumerate your font list), the locale Intl uses for number and date formatting, the UTC offset from getTimezoneOffset(), and the OS guessed from your User Agent. These are ordinary signals any page can read; the tool simply gathers them so you can see which region your browser presents as. Everything runs locally — no requests are sent.

  • Timezone and language carry the most weight — they are the traits most often left inconsistent at the OS level and the most visible.
  • Font detection is width-probing for a few common Chinese fonts; it cannot enumerate everything you have installed.
  • The emoji / OS row is guessed from the User Agent and is a weak signal — do not over-read it.
  • For the network layer (exit IP, WebRTC leaks, whether your timezone matches your IP) pair this with the Proxy Leak Test tool.

FAQ

1. Why does Claude display a region restriction error even with a US proxy IP?

Anthropic inspects more than IP locations: it evaluates JavaScript Intl timezones, Accept-Language order, and WebGL GPU renderers. A timezone mismatch (e.g. US IP with UTC+8 system time) triggers automated security flags.

2. How does this tool detect WebGL GPU fingerprints and VM signatures?

The scanner inspects the UNMASKED_RENDERER_WEBGL string from your graphics context. Virtual environments or headless browsers output software renderers like SwiftShader or llvmpipe, signaling automated sessions.

3. Are environment audit metrics sent to the PocketKit API?

No. Timezone, language and WebGL checks run in the current browser. Browser extensions or proxy settings can still affect the result.

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