In my head. Most my routes I've done for years to know the mileage or can easily add on a couple miles here and there. I don't technically ever plan a run out, it's more on feel in the day & time if that makes sense. Or I just run for time too. Progess I don't track, I mean I know my PRs for my full & current half, but it gets foggy for like 5ks & 10ks, I'm slower than I used to be so I just go with it. I've got Excel setup, let's see how long it lasts, as I really want to track my shoe mileage just out of curiousity, I can estimate it though roughly now anyway.