Alix Earle Flashes Underboob in Tiny Bikini After Braxton Berrios Breakup

Alix Earle officially hit the quarter-century mark Tuesday ... and she celebrated by giving onlookers at the beach a gift -- an unobstructed view of some major underboob!

The social media star and her pals enjoyed some sun, surf, and sand down in Los Cabos, Mexico ... with Earle drinking in some rays in just a tiny brown bikini top, leaving little to the imagination.

AE threw on a pair of nearly see-through white pants and thin sunglasses to complete the outfit ... though we imagine it will be hard for some to tear their eyes away from her top.

Earle looked relaxed as she took selfies with friends ... a grin on her face while she stood in the middle of her crew -- with no indication she's just gone through an extremely difficult breakup.

As you know ... Alix and her longtime beau Braxton Berrios broke up earlier this month -- with Earle insisting physical distance played a role in their split.

Earle defended Braxton -- who was catching some flak online after he posted to social media for the first time since news of the breakup came out -- by referring to him as a best friend and asking her fans not to go after the guy.