Shawn Mendes Shows Off Ripped Muscles In New Shirtless Photos

Shawn Mendes says he's still figuring out his sexuality, but he does have one thing figured out ... he looks damn good without a shirt.

The singer-songwriter ditched his shirt again Thursday while checking out his Halloween decorations at his home in Los Angeles ... showing off his tattoos and his rock-hard abs.

We've seen Shawn more and more since he addressed years-long speculation about his sexuality earlier this week during a concert at the famous Red Rocks Amphitheatre in Colorado ... and, he looks happy after getting a huge weight off his chest.

Judging by Shawn's bulging muscles, he definitely lifts weights off his chest in the gym ... dude is jacked and in great shape.