The Euro 2024 hosts were in freefall last month as they suffered a shock 4-1 loss at home to Japan but were sharp in attack as goals from Ilkay Gundogan, Niclas Fullkrug and Jamal Musiala secured the win in East Hartford, Connecticut.
USA captain Christian Pulisic thrilled the home crowd when he opened the scoring but the Americans could not hold onto their lead and midfielder Gundogan levelled before half-time while Fullkrug and Musiala struck after the break.
"We had a great start to the game, I think the energy levels were high," said US midfielder Weston McKennie.
"I'm sure they went inside (at halftime) and saw how they could hurt us."
Pulisic carved through the German defence and powered a superb shot into the top right corner to put the US in front after 27 minutes, sending the crowd into a frenzy.
But Germany shut the party down 12 minutes later when US keeper Matt Turner dived to intercept the ball from winger Leroy Sane but failed to hold onto it and could only watch helplessly, flat on the ground, as Gundogan tapped home the equaliser.
Turner thwarted an attempt by Fullkrug in the 49th minute but the striker then powered a shot into the bottom right corner to give Germany the advantage just before the hour.
Three minutes later attacking midfielder Musiala fired another shot into the net after a neat flick from Fullkrug.
The US were eager to prove they could compete against the world’s best as they prepare to co-host the 2026 World Cup but McKennie acknowledged that their level dropped after half-time.
"We kind of got a little bit disorganised," he said.
"We couldn't really get close and we were just defending in our box the whole time."
It was the first start midfielder Gio Reyna was handed under Gregg Berhalter since last year's World Cup after a bitter public dispute between the coach and the promising youngster.
The USA next play Ghana in a friendly in Nashville, Tennessee on Tuesday when Germany face Mexico in Philadelphia.
