What is happening vs What's up?

When to use each in English, with meaning, register, and examples.

What is happening

Top 2,000 (common)

What's up?

InformalTop 2,000 (common)
Most formal: What is happening
 What is happeningWhat's up?
Pronunciation🇬🇧 //wɒt ɪz ˈhæpənɪŋ//🇺🇸 //wɑt ɪz ˈhæpənɪŋ//🇬🇧 //wɒts ʌp//🇺🇸 //wɑts ʌp//
MeaningA phrase asking about current events or situations.A casual way to ask someone how they are or what's happening.
ExampleAs I walked into the room, I asked, 'What is happening?'When I saw my friend, I casually said, 'What's up?'
RegisterNeutralInformal
How commonTop 2,000 (common)Top 2,000 (common)
Collocationswhat is happening now, what is happening here, what is happening todayWhat's up, buddy?, What's up, man?, What's up with that?, Hey, what's up?, So, what's up?
Common mistakesOmitting 'is' when asking., Using past tense instead of present., Confusing with 'What happened?' which inquires about completed events.Using it in a formal meeting where a respectful greeting is expected., Misunderstanding it as a question requiring a detailed answer., Not responding appropriately with a casual reply.
Usage notesUse this phrase to inquire about ongoing situations or events, suitable in casual or formal contexts.Used mainly in casual conversations among friends. It may not be appropriate in formal situations.

See it in real clips

What is happening
What's up?

Frequently asked questions: What is happening vs What's up?

What's the difference between What is happening and What's up??

What is happening: A phrase asking about current events or situations. What's up?: A casual way to ask someone how they are or what's happening.

Which is more formal: What is happening and What's up??

What is happening is the most formal of these.

Can you show an example of each?

What is happening: As I walked into the room, I asked, 'What is happening?' What's up?: When I saw my friend, I casually said, 'What's up?'

Can I use What is happening and What's up? interchangeably?

Not always. What is happening and What's up? are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

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