Cool vs That'd be swell

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

Cool

InformalTop 1,000 (very common)A1adjective

That'd be swell

InformalTop 5,000 (fairly common)
Most common: Cool
 CoolThat'd be swell
Pronunciation🇬🇧 /["/kuːl/"]/🇺🇸 /["/kuːl/"]/🇬🇧 //ðætəd bi: swɛl//🇺🇸 //ðætəd bi: swɛl//
MeaningSomething that is good or impressive.That would be great.
ExampleThe weather is really cool today.Getting that promotion? That'd be swell!
RegisterInformalInformal
How commonTop 1,000 (very common)Top 5,000 (fairly common)
CEFR levelA1-
Part of speechadjective
Collocationsbe, feel, look, very, a little, slightly, be, look, sound, extremely, fairly, very, be, look, sound, extremely, fairly, very, appear, be, look, very, pretty, about, with, cool, calm and collected, act, appear, be, distinctly, very, rather, about, towards/​toward, appear, be, look, very, pretty, about, with, cool, calm and collectedthat'd be great, that'd be awesome, that'd be cool
Antonymsuncool, boring, uninteresting-
Common mistakesUsing 'cool' to describe temperatures or weather instead of mood or style., Confusing 'cool' with 'great' in contexts where a specific feeling is implied., Overusing 'cool' in formal or academic situations where more precise vocabulary is needed.Overuse in serious conversations where a formal tone is required., Using the word 'swell' in a negative context.
Usage notesUse 'cool' to describe things that are stylish or admirable. It's very informal, so avoid it in formal writing or conversations. Can imply calmness in some contexts.Used in casual conversations to express enthusiasm or approval. Avoid in formal settings.

See it in real clips

Cool
That'd be swell

Frequently asked questions: Cool vs That'd be swell

What's the difference between Cool and That'd be swell?

Cool: Something that is good or impressive. That'd be swell: That would be great.

Which is more common: Cool and That'd be swell?

Cool is the most common in everyday English.

Can you show an example of each?

Cool: The weather is really cool today. That'd be swell: Getting that promotion? That'd be swell!

Can I use Cool and That'd be swell interchangeably?

Not always. Cool and That'd be swell 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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