9 Ways to ask "How are you?"

Formal

These are appropriate to use with people that you don't know well, and people in your office and people whom you meet when you are working.

1. How are you?/Hi, How're ye?
2. How's it going?/How's it goin'  (= How's it your life?)
3. How (are) you doing?

Informal 

These are appropriate to use with close friends/people who are the same ages with you. They are almost like Slang. You hear them all the time in the daily life if you speak with native speaker regularly.

1. What's up? / 's up?
2. What's good?
3. What's going on? / What's goin' on?

Real Questions (not just greetings)

These are used when you actually want to know about somebody.

1. How are things? How's thing? (How is everything in your life? Give me information.
2. How have you been? How've you been? Tell me about the whole things since the last time I saw you.
3. What have you been up to? (You really asking what have you been doing since the last time I saw you? This one is a lot more informal. It is not appropriate to use with the people much older than you.