Is it legal for an employer to ask in a job interview How old are you?

yes, they need to know if your legal to work the amount of hours they require. the younger u are the less your able to do.

No, they can not ask your age or date of birth on a job application, nor can they ask what year you attended high school or graduated from high school, because that could actually tell them how old you are. These are considered to be illegal questions. However , they can ask if you are over a certain age, like: Are you over 18? Those fall under a protected clause, and pertains to your civil rights. The only time this can take place is after they have hired you, on your employee paperwork.