Formal:
* Sayonara (さよなら) - This is the most common and widely used phrase, similar to "goodbye" in English.
* O-genki de (お元気で) - This literally translates to "Stay healthy," and is used in more formal settings, especially when parting with someone you may not see again for a while.
Informal:
* Jā ne (じゃあね) - A casual way to say "see you later."
* Mata ne (またね) - Means "see you again," often used among friends.
* Itsu demo (いつでも) - Means "anytime," used in a friendly way to imply a willingness to meet again.
Other options:
* Shitsurei shimasu (失礼します) - This literally means "I'm being rude," but is commonly used as a polite way of saying "excuse me" or "goodbye" when leaving a place.
* Kudasai (ください) - This means "please," and can be used as a way of saying "goodbye" in a polite way, particularly in a service setting.
The best way to choose the right expression depends on your relationship with the person you're saying goodbye to and the situation you're in.