Dictionary / Japanese / Good luck
How to Say "Good luck" in Japanese
頑張ってください
ganbatte kudasai
Literally: Please do your best
頑張って
do your best, keep going
ください
please
Polite or casual
Polite頑張ってください
Casual頑張って (ganbatte) / 頑張れ (ganbare)
頑張ってください is polite and works with classmates, colleagues and people you have just met. With friends and family, say 頑張って or 頑張ってね. 頑張れ (ganbare) is the plain command form: direct and casual, and often shouted at sports matches. With someone senior, such as a boss or a teacher, even 頑張ってください can sound a little like you are telling them to try harder, so many people say 応援しています (ōen shite imasu), I am rooting for you. 幸運を祈ります (kōun o inorimasu), I wish you good fortune, is correct but sounds stiff in everyday speech.
Correct
頑張ってください
What people say wrong
頑張れ
Go for it. Fine with friends, too blunt for a teacher or a boss.
The mistake to avoid. 頑張って does not mean luck. It means do your best, keep going. When English speakers wish someone luck, Japanese speakers usually encourage their effort instead, so 頑張って is what friends say before an exam or an interview. 頑張って and 頑張れ say the same thing, but 頑張れ is a plain command and sounds more forceful. If you want to talk about luck itself, 幸運を祈ります exists, but it sounds formal, and you rarely hear it in conversation.
In context
明日の試験、頑張ってね。
Ashita no shiken, ganbatte ne.
Good luck with your exam tomorrow. (casual)
面接、頑張ってください。
Mensetsu, ganbatte kudasai.
Good luck with your interview.
頑張れ、もう少しだ。
Ganbare, mō sukoshi da.
Keep going, you are nearly there. (casual, direct)