How do you say its not possible in french?

There are a few ways to say "it's not possible" in French, depending on the context and formality:

Formal:

* Ce n'est pas possible. (This is the most literal and common translation)

* Cela n'est pas possible. (Slightly more formal than the previous one, using "cela" instead of "ce")

* Il est impossible. (It is impossible)

* C'est impossible. (This is impossible)

Informal:

* C'est pas possible. (This is not possible, spoken form of "Ce n'est pas possible")

* Pas possible. (Not possible, even more informal)

* Impossible. (Impossible)

More specific:

* C'est impossible pour moi. (It's impossible for me)

* Je ne peux pas. (I cannot)

The best choice will depend on the situation and the level of formality you need to maintain.