No cookies, no login. Your browser gives you away just by loading a page. Here are seven signals it leaks, what actually helps with each one, and at the bottom — what yours is leaking right now.
Every site you visit sees where you're connecting from. That's how it knows where to send the page back — but it also reveals roughly where you are and who your provider is.
A VPN or Tor swaps it for a different address. It only hides this one thing though — the other six signals don't care about your IP at all.
WebRTC is what makes video calls work in the browser. To connect two people it swaps network addresses in the background — and a page can grab them. That includes your local IP like 192.168.x.x, and yep, sometimes even your real public IP behind a VPN, because WebRTC can slip past the tunnel.
Firefox: go to about:config → media.peerconnection.enabled → false (breaks video calls). Chrome/Brave: grab an extension like "WebRTC Leak Prevent" or crank up Brave's shields to strict.
Your browser is asked to paint a hidden image no one ever sees. How your GPU and drivers render it is slightly different from everyone else's — and that's enough to ID you without any cookies.
Firefox: privacy.resistFingerprinting in about:config. Tor Browser does it by default and just adds noise to the canvas. Brave does it too. Or install something like CanvasBlocker.
Same trick, but with sound. The Web Audio API generates a tiny waveform you never hear, and little hardware quirks make the result a bit different for every device.
Mostly the same fix as canvas — if you turn on resistFingerprinting, use Tor or Brave, you're covered for both.
A site renders text in dozens of fonts and measures how wide it gets. If a font isn't there, your system falls back to another one and the width gives it away. That whole set can be pretty unique, especially if you work with design and have a lot of fonts installed.
Tor Browser fakes the same font list for everyone, so it's useless there. Outside Tor there's no clean fix — just don't install fonts you don't need.
Ask nicely and your browser will tell a site what graphics card you have. It's meant for games and performance tweaks, but it's also one more near-unique data point.
Firefox: webgl.disabled in about:config (will break games, maps, anything 3D). Tor Browser blocks it completely.
None of these on its own identifies you. Plenty of people have the same graphics card or timezone. But stack them — GPU + canvas + audio + fonts + timezone + screen size — and suddenly almost no one shares the same combo. That's the "device ID" you'll see below.
There's no single switch. The only thing that really works is a browser that makes everyone look the same by default. Tor Browser is still the best at that.
Click the button and this page will run those seven checks right here in your browser. Only your public IP is looked up externally (api.ipify.org) — the rest never leaves this page.
Everything runs locally in your browser. The only thing that leaves is the public IP lookup via
api.ipify.org. History is kept in localStorage on this device and never sent anywhere.
Seven signals, no hidden tracking. It's just HTML / CSS / JS — view source if you want.