33 yes-no questions which each split the audience in half, uniquely identifies slightly more than the world population.

But any given website is much tighter than that: a regular visitor to Cambridge Evening News is unlikely to be based in राजनांदगांव, and vice versa.

Someone is regularly accessing the website of one local take-away restaurant in Larnaca, a gay men-only dating website, and Ars Technica? That’s probably already got you down to 2-15 people out of the ~3e9 on the internet, with just three specific websites in their history.