Fuck should I know vs Not a clue

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

Fuck should I know

SlangBeyond 10,000 (less common)

Not a clue

InformalTop 2,000 (common)
Most formal: Not a clueMost common: Not a clue
 Fuck should I knowNot a clue
Pronunciation🇬🇧 //fʌk ʃəd aɪ nəʊ//🇺🇸 //fʌk ʃəd aɪ noʊ//🇬🇧 //nɒt ə kluː//🇺🇸 //nɑt ə klu//
MeaningA phrase used when someone doesn't have the answer to a question.I don't know anything about it.
ExampleWhat time does the train leave? Fuck should I know!I have not a clue where my keys are.
RegisterSlangInformal
How commonBeyond 10,000 (less common)Top 2,000 (common)
Collocationsfuck should I know, where the hell, what the hell, why the fuck, who the hellnot a clue about, not a clue how, not a clue where
Antonyms-completely sure, certain, fully informed, aware
Common mistakesUsing it in formal situations or with strangers., Confusing with other phrases that express uncertainty., Not understanding the vulgarity can lead to inappropriate usage.Confused with 'have a clue' (meaning to know something)., Incorrectly using in formal contexts., Misplacing 'not' (e.g., saying 'have not a clue').
Usage notesThis phrase is very informal and often used to express frustration or confusion. It may come off as rude, so it's best used among friends or in casual contexts.Used in casual conversation to express ignorance about a topic. Not suitable for formal writing.

See it in real clips

Fuck should I know
Not a clue

Frequently asked questions: Fuck should I know vs Not a clue

What's the difference between Fuck should I know and Not a clue?

Fuck should I know: A phrase used when someone doesn't have the answer to a question. Not a clue: I don't know anything about it.

Which is more formal: Fuck should I know and Not a clue?

Not a clue is the most formal of these.

Which is more common: Fuck should I know and Not a clue?

Not a clue is the most common in everyday English.

Can you show an example of each?

Fuck should I know: What time does the train leave? Fuck should I know! Not a clue: I have not a clue where my keys are.

Can I use Fuck should I know and Not a clue interchangeably?

Not always. Fuck should I know and Not a clue 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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