How much caffeine does v have in it?

Please clarify what you mean by "V". There are many possibilities, including:

* Vitamin V: There is no vitamin called "V".

* A brand of drink: There are many drinks with "V" in their name, like Vitamin Water, V8, or even energy drinks.

* An abbreviation: "V" could be an abbreviation for a specific drink or product.

To answer your question about caffeine, I need more information. Please provide me with the full name or more context about the "V" you are asking about.