What up vs Yo

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

What up

InformalTop 2,000 (common)

Yo

InformalTop 2,000 (common)A1
 What upYo
Pronunciation🇬🇧 //wɒt ʌp//🇺🇸 //wɑt ʌp//🇬🇧 //jəʊ//🇺🇸 //joʊ//
MeaningA casual greeting or question asking how someone is doing.A casual greeting or way to get someone's attention.
ExampleWhen I saw my friend, I said, 'What up!'Yo, are you coming to the party tonight?
RegisterInformalInformal
How commonTop 2,000 (common)Top 2,000 (common)
CEFR level-A1
CollocationsWhat up with you?, Say what up, What up homiesay yo, shout yo, yo dude, yo man, yo what's up
Common mistakesUsing 'What up?' in formal emails., Confusing with 'What's up?' which is more common., Not using it with close friends or people you know well.Using 'yo' in formal emails or speeches., Mispronouncing it as 'yoe'., Confusing it with other greetings like 'hello' or 'hey'.
Usage notesUsed among friends or acquaintances in casual settings; not appropriate for formal occasions.Typically used among friends or in casual settings. Not suitable for formal occasions or with people you don't know well.

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What up
Yo

Frequently asked questions: What up vs Yo

What's the difference between What up and Yo?

What up: A casual greeting or question asking how someone is doing. Yo: A casual greeting or way to get someone's attention.

Can you show an example of each?

What up: When I saw my friend, I said, 'What up!' Yo: Yo, are you coming to the party tonight?

Can I use What up and Yo interchangeably?

Not always. What up and Yo 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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