Like “lol”, it is used when someone says something funny. Personally I would use “lmfao” over “lol” in a situation where I am literally laughing out loud. “lmfao” has a stronger connotation than “lol”, so people generally use it in response to something that they find particularly funny.

What do you use LMAO for?

Lmao stands for laughing my ass off. Typically people use it in written conversations to show that they think something is funny. You can think of it as a stronger version of lol, which stands for laughing out loud.

What does it mean if a guy says lmfao?

If someone tells you something really funny, all you have to do is respond with "lmfao". It's like a more intense, "lol". lol = laughing out loud. rofl = rolling on the floor laughing. lmao = laughing my ass off.