Billie Eilish Holds Lit Firework in Bikini for Fourth of July Weekend

Billie Eilish lit up the internet with her recent post ... posting a pic of herself holding a lit firework -- with just a bikini and towel covering her up!

The singer-songwriter posted the photo Saturday as part of a longer photo series showing her and her friends celebrating America's Independence Day ... or, at least so it would seem from all the fireworks the group had.

Other snaps show the Grammy winner getting ready in the mirror and snuggling with another person on the floor. There's also a clip showing one of her friends holding a firework similar to hers ... so, clearly plenty to go around.

She let her pictures -- many of which are pretty out there -- do the talking ... captioning the post with a simple pair of dynamite emojis.

It's a good thing Billie is living it up this summer 'cause soon she's gotta put her nose to the grindstone once more.

The two-time Oscar winner kicks off her "Hit Me Hard and Soft" tour in September in Quebec and she's got domestic and international dates set up pretty consistently until the middle of next year.