Made a page that shows what a website can tell about your browser before you log in (open source)

Hi all, new here.

Disclosure first: I built this. who.1ms.dog (“Who Are You”) is one of my small network tools under 1ms.dog. Free, no account, MIT source: github.com/yt1988/who-are-you. I had AI help polishing this English text; replies in the thread are mine.

The idea came from the same kind of discussion as the “purposing browsers” thread here: people keep one browser for banking, one for daily stuff, maybe a VPN on top, and assume each one looks like a different person. Often it doesn’t. A VPN only swaps the IP. Fonts, GPU string, screen size and refresh rate, timezone and language all come straight from the browser, and on a Linux desktop that combination is already rare.

What the page shows:

  • exit IP (v4 or v6), ASN/provider, rough location
  • which DNS resolver actually answers for you, and whether it sits in the same country as the exit IP
  • whether system timezone and browser language fit the IP
  • canvas / fonts / WebGL / screen fingerprint, and how rare the combo is among visitors so far
  • where those signals contradict each other (the usual “VPN in one country, clock in another” tell)

Fun comparisons on an Arch box: stock Chromium vs. Firefox with privacy.resistFingerprinting, Mullvad/Tor Browser defaults, Helium or Brave, and system-wide WireGuard vs. a browser proxy extension.

Known limitations:

  • empty without JavaScript
  • behind Cloudflare, so it’s partly blocked in Russia
  • on an IPv6 connection it doesn’t check your IPv4 exit separately
  • the A/B/C grade means “how consistent you look”, not “how safe you are”; Tor + VPN gets a worse grade with nothing actually leaking
  • “unique” is among this page’s visitors only
  • anonymous counting can be switched off on the page; with GPC on nothing is counted

If it gets your setup wrong (DE, Wayland vs X11, odd DNS like unbound/dnscrypt-proxy), I’d like to hear about it.

Yang