Login or register (free and only takes a few minutes) to participate in this question.
You will also have access to many other tools and opportunities designed for those who have language-related jobs (or are passionate about them). Participation is free and the site has a strict confidentiality policy.
Explanation: I suppose you're looking for the translation INTO Slovenian, for you provided the english "happy birthday".
If you want to congratulate somebody on his/her birthday, you say: "vse najbolje" (= "all the best"), and you might add "za rojstni dan" (= "to your birthday"), which is not necessarily to be used
(in the above section, my computer doesn't allow me to provide the character "", so I marked it as "*s")