Impossible to tell really. Maybe around 1200-1300 but the player strength of real life differs along with the fact that USCF uses elo and chess.com glicko.
Rating

It's different for everyone. Some players spend a long time on their games moving pieces around a lot to analyse while others just play from the screen without too much thought.
chess.com's ratings are inflated though. Your USCF rating would likely be at least a few hundred points below whatever your best turn based is.
Some say chess.com blitz for live chess is more accurate (3-10 minute chess or something like that), but if you've never played blitz it wouldn't be a good measurement for you :)
My current rating by Chess.Com is about 1500.
Can someone tell me what is the approximate equivalent rating by US Chess Association?
Many thanks, Arie