Microsoft is quietly building the tools to check your age every time you open a program on Windows, and it's bad news for privacy and for anyone who wants to own their computer rather than rent access to it.

• New Windows code found in September 2026 lets any app ask your system for your age bracket (under 10, 10-17, or 18+), tied to whether you're signed into a Microsoft account.
• California's new child-safety law, kicking in January 2027, forces operating systems to report this age signal, with real fines for companies that don't comply — and similar laws are already moving in Illinois, Colorado, and Brazil.
• Microsoft has spent two years closing off ways to set up Windows without a Microsoft account, meaning you'll likely need to be logged in and tracked for the age check to work at all.
• On work or school computers, IT administrators — not you — control what age Windows reports, meaning your own access can be overridden by someone else.
• Even Linux, often seen as an escape from this kind of tracking, added an age field to its core user system in March 2026, citing the same state laws.

Outlook: Expect the age-check system to go fully live alongside California's law in 2027, with other states and countries likely to adopt similar rules, making it harder to avoid logging in just to use your own computer.