By default, a lot. However, they also are (or at least used to be, it seems to be quite outdated now) really good at documenting their telemetry publicly: https

By default, a lot. However, they also are (or at least used to be, it seems to be quite outdated now) really good at documenting their telemetry publicly: https://www.google.com/chrome/privacy/whitepaper.html https://www.google.com/chrome/privacy/whitepaper.html (I haven't checked whether the documentation is complete/accurate, of course.)