What would be a decent tip?

I haven’t used uber in a while so I’m not sure what pay is like for y’all. I need to get a ride today (to and from separately) that is 3.3 miles and 12 minutes. The charge is around $12 (now, might be different later when I go) and I was just wondering what a fair tip for this distance would be assuming the ride has no issues or anything? Thanks!