3 ms·

Don't huge swaths of people have the same resolution, though? Yes, I understand other things come into play here (OS, Browser, available plugins, etc) but I am

• uxp100 8y ago
  Not if the browser is not full screen, this is resolution/size of browser window.
  • helb 8y ago
    Nope, you can get the screen size, too: > window.outerWidth 1168 > screen.width 1920
• tripzilch 8y ago
  It's all about the bits. You need 33 bits to identify 8 billion people. All that is required is for these bits to be independently uniformly distributed. Say everybody uses one of four resolutions equally. That's two bits: 00, 01, 10 and 11. Now let's say that people's gender is also binary, distributed 50/50 and independent from what resolution someone uses. You can just tack that bit onto the two you already got and now you have three (the ability to distinguish between 2^3 = 8 individuals). I won't go into the details, but if you have an estimate for the probability distribution of browser resolutions, it's fairly easy to extract the proper amount of bits of entropy. Being independent is a bit harder to make sure of, but as long as you pick things which aren't too obviously correlated, you can just take a safety margin and use, say, 40 bits to identify people, and it's probably fine (and for tracking purposes, a false positive isn't the end of the world, either). That said, while I support the concept and idea behind panopticlick, I've always felt it overestimated the unicity of my browser. Or maybe I just really underestimate it myself. I don't know.