Most of my friends I’ve had for 5+ years. They are only now discovering I have a large penis, because we have only just started going to the pool and the beach together, and my wet shorts make an obvious outline. Or maybe they always knew and never commented until now. Who knows. Before then, only a small number of 5-6 people knew, either by seeing on Grindr that I was advertising myself as hung, or accidental bulge showing.
How about everyone else? Do you advertise it openly, or perhaps previous partners have shared that information with your circle?