Maybe not that fast vs Slow down

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

Maybe not that fast

Beyond 10,000 (less common)

Slow down

Top 2,000 (common)
Most common: Slow down
 Maybe not that fastSlow down
Pronunciation🇬🇧 //ˈmeɪbi nɒt ðæt fɑːst//🇺🇸 //ˈmeɪbi nɑːt ðæt fæst//🇬🇧 //sləʊ daʊn//🇺🇸 //sloʊ daʊn//
MeaningA suggestion to slow down or reconsider speed.To reduce speed or to take things easier.
ExampleI understand you're excited, but maybe not that fast when you're driving.Please slow down when driving through the school zone.
RegisterNeutralNeutral
How commonBeyond 10,000 (less common)Top 2,000 (common)
Collocationsmaybe not that quick, move maybe not that fast, suggest maybe not that fast, respond maybe not that fast, say maybe not that fastslow down a bit, slow down traffic, slow down the pace, slow down for safety
Common mistakesUsing it without context, making it unclear., Confusing it with similar phrases like 'Not that fast.', Inappropriately using in formal settings where a more direct phrase is better.Using 'slow down' in a literal sense only, ignoring its figurative uses., Confusing with 'slowly' which is an adverb., Incorrectly using 'slow down' without an object when it's needed for clarity.
Usage notesUse this phrase when suggesting a slower pace is better. It's appropriate in casual and formal discussions, especially when safety or thoroughness matters.Use 'slow down' when advising someone to reduce their pace. Can be informal in day-to-day conversation, but is still suitable in general contexts. Avoid using it in very formal writing.

See it in real clips

Maybe not that fast
Slow down

Frequently asked questions: Maybe not that fast vs Slow down

What's the difference between Maybe not that fast and Slow down?

Maybe not that fast: A suggestion to slow down or reconsider speed. Slow down: To reduce speed or to take things easier.

Which is more common: Maybe not that fast and Slow down?

Slow down is the most common in everyday English.

Can you show an example of each?

Maybe not that fast: I understand you're excited, but maybe not that fast when you're driving. Slow down: Please slow down when driving through the school zone.

Can I use Maybe not that fast and Slow down interchangeably?

Not always. Maybe not that fast and Slow down 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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