I'm joking vs Just kidding

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

I'm joking

InformalTop 2,000 (common)

Just kidding

InformalTop 2,000 (common)
 I'm jokingJust kidding
Pronunciation🇬🇧 //aɪm ˈdʒoʊ.kɪŋ//🇺🇸 //aɪm ˈdʒoʊ.kɪŋ//🇬🇧 //dʒʌst ˈkɪdɪŋ//🇺🇸 //dʒʌst ˈkɪdɪŋ//
MeaningI am not serious; I am saying something funny.I didn't mean what I just said.
ExampleI can't believe you thought I was serious! I’m joking.I really thought you were serious about that! Oh wait, you were just kidding.
RegisterInformalInformal
How commonTop 2,000 (common)Top 2,000 (common)
Collocationsmake a joke, lighten the mood, playfully teasing, not serious, tell a jokejust kidding around, just kidding, right?, don't take it seriously
Antonyms-seriously, no joke, for real, honestly
Common mistakesUsed too seriously when it's meant to be light-hearted., Confused with 'I'm serious' which has the opposite meaning.Using in formal situations., Confusing with 'just joking'., Overusing can make it sound insincere.
Usage notesUsed casually in conversations to lighten the mood after a serious statement. Avoid in formal settings.Used to lighten the mood after a serious or surprising statement. Best for casual conversations; avoid in formal contexts.

See it in real clips

I'm joking
Just kidding

Frequently asked questions: I'm joking vs Just kidding

What's the difference between I'm joking and Just kidding?

I'm joking: I am not serious; I am saying something funny. Just kidding: I didn't mean what I just said.

Can you show an example of each?

I'm joking: I can't believe you thought I was serious! I’m joking. Just kidding: I really thought you were serious about that! Oh wait, you were just kidding.

Can I use I'm joking and Just kidding interchangeably?

Not always. I'm joking and Just kidding 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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