Affirm vs Confirm

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

Affirm

Top 3,000 (common)B1verb

Confirm

Top 2,000 (common)B1verb
Most common: Confirm
 AffirmConfirm
Pronunciation🇬🇧 /["/əˈfɜːm/","/əˈfɜːmz/","/əˈfɜːmd/","/əˈfɜːmɪŋ/"]/🇺🇸 /["/əˈfɜːrm/","/əˈfɜːrmz/","/əˈfɜːrmd/","/əˈfɜːrmɪŋ/"]/🇬🇧 //kənˈfɜːm//🇺🇸 //kənˈfɜrm//
MeaningTo say that something is true or to support it.To say that something is true or to make sure of it.
ExampleBoth sides affirmed their commitment to the ceasefire.Can you confirm the time for the meeting tomorrow?
RegisterNeutralNeutral
How commonTop 3,000 (common)Top 2,000 (common)
CEFR levelB1B1
Part of speechverbverb
Collocationsaffirm one's beliefs, affirm a statement, affirm support, affirm a decision, affirm the truthconfirm a reservation, confirm an appointment, confirm information, confirm a hypothesis, confirm results
Antonymsdeny, reject, disputedeny, disprove, reject
Common mistakesConfused with 'confirm'—they have similar meanings but different usages., Using 'affirm' without an object (e.g., saying 'I affirm' instead of 'I affirm my support')., Incorrectly using 'affirm' in negative contexts.Confused with 'affirm' which is more formal., Using 'confirm' without an object in sentences., Incorrectly assuming 'confirmed' is always followed by a date.
Usage notesUse 'affirm' in contexts that require a supportive or confirming statement. It's appropriate in formal discussions, but less so in casual conversations, where simpler words like 'say' or 'agree' might work better.Use 'confirm' in both formal and informal contexts, such as meetings or casual conversations. It's appropriate when verifying information or giving approval.

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Confirm

Frequently asked questions: Affirm vs Confirm

What's the difference between Affirm and Confirm?

Affirm: To say that something is true or to support it. Confirm: To say that something is true or to make sure of it.

Which is more common: Affirm and Confirm?

Confirm is the most common in everyday English.

Are Affirm and Confirm the same CEFR level?

Affirm: B1, Confirm: B1 on the CEFR scale.

What part of speech are Affirm and Confirm?

Affirm: verb, Confirm: verb.

Can you show an example of each?

Affirm: Both sides affirmed their commitment to the ceasefire. Confirm: Can you confirm the time for the meeting tomorrow?

Can I use Affirm and Confirm interchangeably?

Not always. Affirm and Confirm 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.