Formal:
* Elle a raison. (This is the most common and neutral translation.)
* Elle a juste. (This emphasizes that she is right.)
* Elle a bien raison. (This is a stronger way of saying she is right, emphasizing agreement.)
Informal:
* Elle a tout à fait raison. (This is a more emphatic way of saying she is right.)
* Elle a raison de dire ça. (This emphasizes that she is right in what she is saying.)
The best translation will depend on the specific situation and the level of formality you want to convey.