Formal:
* Extraordinaire: This is a good general-purpose word for "amazing" in formal contexts, like describing a performance or an achievement.
* Remarquable: This translates more literally to "remarkable" but is often used to express "amazing" in a more formal setting.
Informal:
* Génial: This is a very common and versatile word for "amazing" in informal settings, like talking to friends.
* Superbe: This means "superb" but is also used to express "amazing" in a more enthusiastic way.
* Fantastique: This is similar to "fantastic" in English and is used for things that are exciting or wonderful.
* Incroyable: This translates literally to "unbelievable," but is also used for things that are amazing in a positive way.
Other options:
* Étonnant: This translates to "astonishing" and is used for something that is unexpected or surprising.
* Impressionnant: This translates to "impressive" and is used for something that is grand or awe-inspiring.
The best word to use will depend on the specific context and the intended meaning.