I guarantee you vs Promise

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

I guarantee you

Top 2,000 (common)

Promise

Top 1,000 (very common)A2verb
Most common: Promise
 I guarantee youPromise
Pronunciation🇬🇧 //aɪ ˈɡærənˌti jʊ//🇺🇸 //aɪ ˈɡærənˌti jʊ//🇬🇧 /["/ˈprɒmɪs/","/ˈprɒmɪsɪz/","/ˈprɒmɪst/","/ˈprɒmɪsɪŋ/"]/🇺🇸 /["/ˈprɑːmɪs/","/ˈprɑːmɪsɪz/","/ˈprɑːmɪst/","/ˈprɑːmɪsɪŋ/"]/
MeaningI promise you that something will happen.A commitment to do something or not do something.
ExampleI guarantee you will love this new restaurant.I promise to help you with your homework.
RegisterNeutralNeutral
How commonTop 2,000 (common)Top 1,000 (very common)
CEFR level-A2
Part of speechverb
Collocationsguarantee satisfaction, guarantee results, guarantee successfaithfully, solemnly, initially, can, cannot, seem to, to, as promised, I can’t promise anything
Antonyms-lie, break, betray
Common mistakesOmitting 'you' and saying 'I guarantee'., Using 'guarantee' with a noun directly instead of a personal pronoun., Confusing with 'ensure' which implies preventing something.Confusing 'promise' with 'vow' or 'pledge' in terms of strength., Using 'promise' without an object (e.g., 'I promise' should specify what)., Misusing in the past tense (e.g., 'I promised' without a follow-up).
Usage notesUse in informal to neutral conversations to assure someone. Avoid in highly formal writing or speeches.Use 'promise' when you want to express a vow or assurance. Common in both spoken and written contexts, but avoid in formal legal documents.

See it in real clips

I guarantee you
Promise

Frequently asked questions: I guarantee you vs Promise

What's the difference between I guarantee you and Promise?

I guarantee you: I promise you that something will happen. Promise: A commitment to do something or not do something.

Which is more common: I guarantee you and Promise?

Promise is the most common in everyday English.

Can you show an example of each?

I guarantee you: I guarantee you will love this new restaurant. Promise: I promise to help you with your homework.

Can I use I guarantee you and Promise interchangeably?

Not always. I guarantee you and Promise 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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