I ask myself that same question about every 6 months as I get lazy and finally decide to unload all the shit from my pockets. The big work ring? Leave it at work. All the backups? Secure at home.

Current rotation is:

1 car key, in my pocket. 1 house key, in my work bag 1 work key, on a belt clip with my work ID card, on my belt. 1 backup work key, in my work bag.

Maximum 2 keys on my person at any one time, and minimal chance of losing more than one of them.

They all live on individual hooks by my front door, so if I get to my car without a car key, I can tell right away that I also don’t have my belt work key, then I shamefully go back inside for both.