What does 'LMAO' mean in texting?

“LMAO” means “laughing my ass off” in texting. It is an emphatic internet initialism used to show that something is extremely funny, amusing, or absurd.

The expression developed alongside early online chat, instant messaging, forums, and text messaging, where shortened phrases saved typing time. LMAO is stronger and more informal than “LOL,” which means “laughing out loud.” It is also commonly extended to “LMFAO,” adding an intensifier, or combined with “ROFL” in “ROFLMAO.”

The wording is deliberately vulgar and casual, so LMAO is usually unsuitable for formal, professional, or polite communication. British users may write “laughing my arse off,” but “ass” is the standard form represented by the stored answer. The phrase does not necessarily mean the writer is literally laughing; like LOL, it can signal amusement, irony, disbelief, or a friendly conversational tone.

Capitalization is not essential: “lmao” and “LMAO” generally carry the same meaning, although uppercase styling can suggest greater emphasis.