It can't be true vs That's impossible

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

It can't be true

Top 2,000 (common)

That's impossible

Top 2,000 (common)
 It can't be trueThat's impossible
Pronunciation🇬🇧 //ɪt kɑːnt bi truː//🇺🇸 //ɪt kænt bi tru//🇬🇧 //ðæts ɪmˈpɒsəbl//🇺🇸 //ðæts ɪmˈpɑsəbl//
MeaningThis is a phrase used to express disbelief about something.It cannot be done.
ExampleWhen I heard the news about the lottery winner, I thought, 'It can't be true!'When I heard his plan, I thought, 'That's impossible.'
RegisterNeutralNeutral
How commonTop 2,000 (common)Top 2,000 (common)
CollocationsIt can't be true that, It can't be true for, It can't be true aboutThat's impossible to believe, That's impossible to achieve, That's impossible to accept
Common mistakesConfusing with 'It can't be possible' which has a different connotation., Using in overly formal writing or speeches where skepticism may not be suitable.Using 'that's impossible' too casually in formal discussions., Confusing the expression with 'it's impossible' when addressing multiple situations., Overusing the phrase for minor challenges.
Usage notesUsed in everyday conversations to convey doubt or skepticism. It is appropriate in most contexts but may sound informal in very serious discussions.Use this phrase to express disbelief or skepticism in a situation. It is suitable for informal and formal situations, but can sound a bit strong depending on tone.

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It can't be true
That's impossible

Frequently asked questions: It can't be true vs That's impossible

What's the difference between It can't be true and That's impossible?

It can't be true: This is a phrase used to express disbelief about something. That's impossible: It cannot be done.

Can you show an example of each?

It can't be true: When I heard the news about the lottery winner, I thought, 'It can't be true!' That's impossible: When I heard his plan, I thought, 'That's impossible.'

Can I use It can't be true and That's impossible interchangeably?

Not always. It can't be true and That's impossible 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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