¿Qué pasa? vs. ¿Qué tal? vs. ¿Qué onda?

Question

What is the difference between "¿Qué pasa?", "¿Qué tal?" and "¿Qué onda?" ?

They all mean and can be translated as "What's up?" in English per my understanding and they are all informal. Are some of them more slang? Are some of them more common in certain Spanish speaking countries/regions? Which one is more common in Spain?

Origins and literal meanings can provide clues but of course, they are idiomatic expressions:

¿Qué onda? literally means "What wave?" and wave can refer to vibrational waves, thus vibes. It is close to "What's the vibe?" (which I don't hear in English but there is some usage online)

¿Qué tal? literally means "What such?" but could mean "To What extent?" as well. (possibly)
More details in this question:
What is the origin of the expression "qué tal"?

¿Qué pasa? literally means "What passes?" or "What happens?". The verb pasar means "to pass" or "to happen" in this context.

Answer 1

¿Qué tal? It's the most general and formal in each Spanish-speaking country, although its use is only intended for someone known in advance, to gain confidence or start a conversation or to break the formality. It's quite global since it's an abbreviation that admits several interpretations: ¿Qué tal van tus cosas? ¿Que tal va todo? ¿Qué tal te va la vida? ¿Qué tal? is always friendly while ¿Qué pasa? can have different meanings depending on the type of tone of voice or emphasis given to it.

For example:

• In a work meeting with unknown people, you don't use ¿Qué tal? as an introduction, but you can use it to break the ice in a general way or to ask how the meeting went at the end when has achieved some confidence. Would mean ¿Qué tal está usted/están ustedes? in the first option and ¿Qué tal ha ido la reunión? (How was the meeting?) in the second.
• A teacher never asks ¿Qué tal? to a student, unless he/she wants to know something about their personal life, or ask about how the school work has been going. ¿Qué tal? it implies trust, either existing or about to be initiated.

¿Qué pasa? is quite informal and a bit more inquisitive than ¿Qué tal? since it asks about what happens to a person, ¿Qué te pasa? or what happens in the environment ¿Qué pasa aquí? It's used among young or very informal people. In Spain it's common to use it jokingly to enter into conversation: What's up man? ¿Qué pasa tío? or to say hello between colleagues.

¿Qué onda? It's mostly used in Latin America and very informal, also an abbreviation for ¿En qué onda estás? (personal) o ¿Qué onda hay aquí? (general) Onda is quite equivalent to mood, whether personal or in the environment.

To me:

¿Qué tal? = How is it going?

¿Qué pasa? = What's up?

I'm living in Spain and the form I use the most is ¿Qué tal? or ¿Qué hay?, always with people I know, never with strangers.

Answer 2

¿Qué onda? definitely feels the most informal of these to me, and so What's up? or something more slangy like How's it hangin'? is how I tend to translate it in my mind. (And the sometimes (and even less formal) pronunciation ¿Quiooonda? turns into Wazzuuup? in my mind.)

I'd additionally say that ¿Qué pasa? can tend to have a connotation of something being wrong, so can sometimes be interpreted as What's the matter? or What's wrong?, usually in a caring sense, but sometimes even aggressively/angrily. For example, depending on the tone of voice, ¿Qué te pasa? could even mean What [the #&@$] is the matter with you? (though I realize the "te" here makes it a bit of a different case). I'd imagine that a lot of where ¿Qué pasa? falls between a neutral _What's going on?" and a negative What's wrong? probably lies in tone of voice or other context, but there could also be differences in regional usage at play that I might not be aware of (I have most experience with Mexican, then Chilean, then northern Central American speakers).

If you're looking for something of a "go-to" option among these choices, I'd agree with Danielillo that ¿Qué tal? works well as a relatively general/neutral/widely-used choice. I'll note though that if you mentally translate it in your mind as What's up? (as I did when first learning Spanish), it can be confusing to hear the typical response of bien (well/good), since as Danielillo (and some responses in the link in your question) mention, I believe it's a shortened form of a longer unstated expression. So I'd agree with him that How's it going? (or How did it go? as the context might dictate) would be a better way of thinking about it.

I'll also throw in an additional variation that I hear less than the above (and I guess is technically a past tense variation of ¿Qué hay?): ¿Qué hubo?. It feels informal/slangy to me, especially when used in variations Qué húbole? or ¿Quihúbole? (the latter feeling similar to me to the aforementioned ¿Quionda?).

Since I'm not a native Spanish speaker though, I'd be happy to be corrected where any of my above interpretations or nuances might have missed the mark.

Answer 3

All correspond to What's up? but not all are greetings.

¿Qué tal? is an informal greeting usable almost everywhere. It can also mean What do you think of this? in a situation, for example, when you're trying out new shoes and want to ask for someone's opinion.

¿Qué onda? is a super informal greeting. Never use it with your boss. It's mostly found in Mexican Spanish and rarely elsewhere. It can also be used to ask What's up with him? if you want to ask for some details of a situation.

¿Qué pasa? is not a greeting. It corresponds to the usage What's up with him? I described in the above paragraph.

Answer 4

We forgot to add " Como estas/esta?" which in my opinion is more common.

At least where I'm from is the standard and none of the others are really used with the exception perhaps of "Que tal?"

To me "Como estas?" sound more proper without being too formal.

Answer 5

I've worked in Mexico quite a bit, a little less in South America, and que onda is actually said in Mexico as qui onda, or "who's waving", not what's waving.
So it's a little vulgar and more specific (obviously) to males. Has nothing to do with vibrations, that's just someone being politically correct. More or less equivalent to "how's it hanging"...