Internet ads migrating to other users' devices!

[fungussingstheblues]

Thought there was a techy forum on here but can't seem to find it... anyway, I was searching for furniture on my computer yesterday (desktop Mac), and ads for the (fairly obscure) shop have suddenly started appearing on DH's Chromebook a few hours later. Why is this, it's infuriating! There's no crossover between logins or anything – he has his Google login, we don't access each other's computers... so why?? How does it knoooww????

I'm worried now as his birthday is coming up and I don't want my searches for a present to appear when he's reading the paper online! (I keep forgetting to turn on the Incognito setting...)

Are you on the same WiFi?. So annoying isn't it!

Same Wifi, yes. So the Wifi somehow reads the pages you visit, then? Gah!

I assumed trageted ads were done via your IP address rather than individual device - google suggests this is true
www.accudata.com/blog/ip-targeting/

Maybe use your phone (switch wifi off) to look for presents?

Thanks, rbe78. I thought each computer had an individual IP address –am I wrong and it's just the router, then? That would explain it, certainly. Will just have to use mobile data or private browsing (if that will work?!).