What is an appropriate response to "what's up" greeting?

Solution 1:

“What’s up?” is a greeting whose meaning is mostly irrelevant in that the asker doesn’t want an answer to the literal question which means something like “What is new?” or “What’s happening (right now/in your life)?”.

The simplest response if you don’t have information you want to share immediately with the asker is probably just to say something like “not much”, “not too much”, or “hey (man/dude)”. If you’re offered “what’s up” in response to a greeting of your own, you should read it as a request for you to proceed to the content part of what you want to talk about.

Solution 2:

"Not much, how about you?"

Unless, of course, you are in the midst of something exceptional.

It's just a greeting meaning "What is happening?", and a reply that nothing's happening means you're fine.

Solution 3:

That is an expression that has about as much meaningfulness as "How are you?" or "How's it going?" All, including "What's up?" are used as greetings. Now, each can be taken literally where someone may want to truly know "how you are", particularly if you've been sick, for instance, but all those terms are very commonly used along with the traditional greeting words, "Hi, "Hello", "Hey".

Responses?

What's up? - "Not much, how about with you?"

How are you? - "Fine, and you?"

How's it going? - "OK. How's it going with you?"

Solution 4:

Depends on the tone in which it's asked - with the right tone, it can be synonymous with "What's wrong?", where, with a less concerned tone, it's more of a "How are you?". I'd reply very similarly to either.

Solution 5:

If you want to be unconventional, you can reply "the sun" or "me, barely." That usually gives people pause.