How do you say in french I hope having fun?

There are a few ways to say "I hope you're having fun" in French, depending on the context and level of formality:

Formal:

* J'espère que vous vous amusez bien. (This is the most formal and polite way to say it.)

Informal:

* J'espère que tu t'amuses bien. (This is used with friends or people you know well.)

* Je te souhaite de bien t'amuser. (This is another informal option that literally means "I wish you to have fun.")

More colloquial options:

* Amuse-toi bien! (This is a very common and informal way to say "Have fun!" and can be used on its own.)

* Passe un bon moment! (This means "Have a good time!" and is also very informal.)

The best way to choose the right phrase depends on your relationship with the person you are talking to.