No kiddin vs Seriously

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

No kiddin

InformalTop 3,000 (common)

Seriously

Top 2,000 (common)B1adverb
Most formal: SeriouslyMost common: Seriously
 No kiddinSeriously
Pronunciation🇬🇧 //nəʊ ˈkɪdɪn//🇺🇸 //noʊ ˈkɪdɪn//🇬🇧 /["/ˈsɪəriəsli/"]/🇺🇸 /["/ˈsɪriəsli/"]/
MeaningReally? Are you serious?used to show that something is true or important
ExampleYou actually won the lottery? No kiddin!I seriously need to improve my math skills before the exam.
RegisterInformalNeutral
How commonTop 3,000 (common)Top 2,000 (common)
CEFR level-B1
Part of speechadverb
CollocationsNo kiddin, really, I mean, no kiddin, Seriously, no kiddinseriously consider, seriously doubt, seriously think, seriously injure
Antonyms-playfully, jokingly
Common mistakesUsed in formal contexts where it sounds inappropriate., Confused with 'No kidding', which has the same meaning., Mispronounced, leading to misunderstandings.Using 'serious' instead of 'seriously' in adverbial contexts., Confusing with 'sincerely' when trying to express genuine feelings.
Usage notesUsed in casual settings to express surprise or disbelief. It's not suitable for formal conversations.Usually used to emphasize seriousness in conversations. It can sound casual in informal settings but is appropriate in serious discussions.

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No kiddin
Seriously

Frequently asked questions: No kiddin vs Seriously

What's the difference between No kiddin and Seriously?

No kiddin: Really? Are you serious? Seriously: used to show that something is true or important

Which is more formal: No kiddin and Seriously?

Seriously is the most formal of these.

Which is more common: No kiddin and Seriously?

Seriously is the most common in everyday English.

Can you show an example of each?

No kiddin: You actually won the lottery? No kiddin! Seriously: I seriously need to improve my math skills before the exam.

Can I use No kiddin and Seriously interchangeably?

Not always. No kiddin and Seriously 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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