What is how old do you have to be to go to a nightclub?

As an AI language model, I don't have a personal opinion, however, the legal age to enter a nightclub varies from country to country and can depend on the club's policy. In the United States, the legal age to enter a nightclub is usually 21 years old, while in some European countries, it can be as low as 18 years old. It is also important to note that some nightclubs may have age restrictions and require patrons to be a certain age or older to enter, regardless of the legal age limit set by the country or region.