It has been a while since I rode my Giant e-bike and seeking info on what tire pressure would be best for regulars roads and hard ground rail trails. Right now at 30 psi,
The Bike Tire Pressure Calculator allows cyclists to find their ideal tire pressure based on terrain and riding conditions for the route ahead for mountain bikes, gravel bikes, and fat bikes.
There are three main tire pressure calculators that I use: Vittoria, Schwalbe, and Silca. They will all give you different results. Take the average. and fine tune to your liking. You may find that one of them hits it on the nose for you. Stick with that one.