What's up?
A very casual, slangy greeting, similar to 'What's the vibe?'. Use with close friends. Very common in Mexico.
A friendly and common alternative, literally 'How are you going?'. Works in most informal situations.
Extremely common in Colombia and Venezuela. It means 'What else?' but is used just like 'What's up?'.
Literally 'What's happening?'. Can mean 'What's up?', but be careful, as it can also mean 'What's wrong?'. Tone and context are key.
Hi, Carlos, what's up?
What's up, friends? Are we going to the beach?
Good morning, ma'am. How is everything going?
You're late. What's wrong?
While '¿Qué tal?' is understood, '¿Qué onda?' is the quintessential casual greeting among friends. You might also hear '¿Qué rollo?' or '¿Qué pex?', which are even more informal slang.
'¿Qué más?' is the go-to greeting here, often even more common than '¿Cómo estás?'. You'll also hear '¿Quiubo?' (a contraction of '¿qué hubo?').
You will frequently hear '¿Cómo andás?', which uses the 'vos' form common in Argentina. '¿Todo bien?' is also a very common way to ask 'What's up?'.
'¿Cómo estai?' (using the Chilean 'voseo' form) is very common. '¿Qué se cuenta?' (What's new?) is also used as a 'what's up?' style greeting.
'¿Qué tal?' and '¿Qué pasa?' are very common. They are used in the same way as in Latin America, but you will hear the 'vosotros' form for groups ('¿Qué tal estáis?').
Translating literally to '¿Qué arriba?'. — This is incorrect. 'What's up?' is an idiom. Its meaning isn't based on the individual words. '¿Qué arriba?' is a nonsensical phrase in Spanish. The correct idiomatic equivalent is '¿Qué tal?'.
Using '¿Qué pasa?' as a light, friendly greeting all the time. — While '¿Qué pasa?' can mean 'What's up?', it often has a sense of 'What's wrong?' or 'What's the matter?'. If someone looks worried and you ask '¿Qué pasa?', you are asking them what is wrong. Stick with '¿Qué tal?' for a neutral, always-safe greeting.
Using regional slang in the wrong country or context. — Saying '¿Qué onda?' in Colombia or '¿Qué más?' in Mexico might cause a little confusion. They'll likely understand you from context, but it will mark you as a foreigner. In formal situations or when you've just met someone, always use a more neutral phrase like '¿Qué tal?' or '¿Cómo está?'.