When deciding what size belt is needed you need to measure properly. On the tongue of the belt there are usually an odd number of holes and it will most often be 7. You would measure to the middle hole.
At the buckle end of the belt you would measure from where the buckle tongue meets the rim of the buckle. If you have an old belt of some kind put it on at the location where you want to wear the belt you want to order. Make it as snug as you want it to be. Keep track of which hole the buckle is in and then measure as indicated and that will be your belt size.