I use the odometer on a bike computer. Be warned, mine is a wireless bike computer. A year or so ago working late, I moved my bike to the door nearest where I was working, to save time when leaving. The bike logged 80 miles without going anywhere. The work wireless was causing it.

That said, Strava has always been weird for me. Usually 1-2% higher than my computer. Part of that is my fault. My phone is in my pocket and logs my steps walking around during a stop. Easier to rely on the computer for miles ridden.