Nice ro read. At home, we use 3 tablets and one television on one Google account. All of us have own Google accounts on own phones. I have different Google account on different machines (linux, mac, win10). The first Google account have some random ads on TV and tablets. Practically without real content for each of us. On phones are more targeted (wife, kids) but still randomised.

The strange thigs come on accounts that are on my working machines. All are on same IP range like other devices, the difference is the OS. All ads are different. Sometimes womans stuff, aliexpress, amazon. Without any logic.

Im coming from a small European country but all ads on working machines are american or chinese (english language). On other devices are in my language.

Any idea?

The work machine differences are interesting. Google uses OS, browser language, and the language of content you consume as profiling signals, not just searches. If your work browsing is mostly English-language sites, Google may be slotting those accounts into a different market entirely. Same IP, but different OS telemetry, different default browser settings, different behavioral fingerprint.

Would be interesting to check myadcenter.google.com on each machine to see how different the profiles actually are.