That was so crazy vs Unbelievable

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

That was so crazy

InformalTop 2,000 (common)

Unbelievable

Top 1,000 (very common)
Most formal: UnbelievableMost common: Unbelievable
 That was so crazyUnbelievable
Pronunciation🇬🇧 //ðæt wəz səʊ ˈkreɪ.zi//🇺🇸 //ðæt wəz soʊ ˈkreɪ.zi//🇬🇧 //ʌn.bɪˈliː.və.bəl//🇺🇸 //ʌn.bɪˈlivə.bəl//
MeaningSomething very surprising or difficult to believe.Not able to be believed; hard to accept as true.
ExampleDid you see that circus performance? That was so crazy!His story about climbing Everest without oxygen was simply unbelievable.
RegisterInformalNeutral
How commonTop 2,000 (common)Top 1,000 (very common)
Collocationsso crazy funny, that was so crazy fun, that was so crazy unexpectedunbelievable story, unbelievable situation, unbelievable coincidence, unbelievable talent, unbelievable prices
Antonyms-credible, believable, plausible
Common mistakesUsing 'crazy' to describe serious issues, which can be seen as insensitive., Misusing 'that' when referring to less specific situations., Using it in overly formal situations, which sounds unnatural.Confused with 'incredible' - both mean similar things but can have different connotations., Used too casually in serious contexts., Often mispronounced by stressing the wrong syllable.
Usage notesUsed in casual conversations to express disbelief or astonishment about a situation. Avoid in formal or academic contexts.Used to express astonishment or disbelief. It can be positive or negative depending on context (e.g., an unbelievable achievement vs. an unbelievable lie).

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That was so crazy
Unbelievable

Frequently asked questions: That was so crazy vs Unbelievable

What's the difference between That was so crazy and Unbelievable?

That was so crazy: Something very surprising or difficult to believe. Unbelievable: Not able to be believed; hard to accept as true.

Which is more formal: That was so crazy and Unbelievable?

Unbelievable is the most formal of these.

Which is more common: That was so crazy and Unbelievable?

Unbelievable is the most common in everyday English.

Can you show an example of each?

That was so crazy: Did you see that circus performance? That was so crazy! Unbelievable: His story about climbing Everest without oxygen was simply unbelievable.

Can I use That was so crazy and Unbelievable interchangeably?

Not always. That was so crazy and Unbelievable 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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