How do you say thats great in French?

There are several ways to say "that's great" in French, depending on the context and the level of formality:

Formal:

* C'est formidable! (This is formidable!)

* C'est excellent! (This is excellent!)

* C'est parfait! (This is perfect!)

* C'est très bien! (This is very good!)

Informal:

* C'est génial! (This is awesome!)

* C'est super! (This is great!)

* C'est top! (This is great!)

* C'est cool! (This is cool!)

* C'est chouette! (This is great!)

* Génial! (Awesome!)

* Super! (Great!)

More specific:

* C'est une bonne nouvelle! (That's good news!)

* Je suis content/contente de l'apprendre! (I'm happy to hear that!)

* Je trouve ça super! (I think that's great!)

The best choice depends on the situation. If you're talking to someone you know well, you can use the more informal options. If you're in a formal setting, stick to the more formal expressions.