How a site decides how old you are. To catch the child, it usually has to look at everyone.
You remember the button: "Yes, I am 18". For a long time that was the whole check. Everyone knew it was a joke. A kid presses the same button, just faster.
Australia decided to end the joke. Its law, assented to in December 2024, says social networks must take "reasonable steps" to keep children under 16 from having accounts. It does not spell out what the steps are. It does spell out what happens if you skip them: a heavy fine, written into the text itself.
In practice there are three routes. The first is a document: an ID card or passport. It is accurate, but it means handing a copy of your ID to a social network. The second is your face: you upload a selfie and software estimates how old you look. The third is the quietest. Software looks at what you write, who you follow, what you like, and draws its own conclusion. Nobody asks you.
The interesting part of the Australian law is what it forbids. A platform cannot demand government ID as the only option. If it asks for ID, it must also offer another reasonable way to show you are 16 or older. And the data collected for the check must be destroyed once it has done its job. The lawmakers saw the trap themselves: protecting children easily becomes an excuse to collect everyone's papers.
The European version
The European Commission started from the other end. On 14 July 2025 it published a blueprint for a tool that lets you prove you are over 18 without sharing any other personal data. No name, no date of birth. Just a yes. It is called the "mini wallet" and it is built on the same technical specifications as the European Digital Identity Wallet. On 15 April 2026 the Commission declared all its features ready, so member states can now adapt it for their own use. It recommends that member states roll out age verification by the end of 2026.
Next time a network announces age checks, ask two things. What exactly does it want from you. And where does that go after the check. The answer tells you more than the ban itself.