Happy birthday, Justin Bieber!

JB turns 19 today — Friday, March 1 — and he celebrated Thursday night after his concert in Birmingham, England.

Bieber loves to show off his abs and torso, but his butt doesn't like to be left out either. He's shirtless, with his blue pants resting just beneath his rear end, revealing his tighty-whities.

According to UK’s The Mirror, Justin plans to celebrate his birthday in London along with 20 friends at a circus-themed event with clowns and a ringmaster. Maybe someone should give him some better-fitting clothes, as a b-day gift?

Sources: The Mirror