Let's learn how to write birthday messages in Japanese! 

誕生日=tanjoubi=birthday
おめでとう=omedetou=means "Congratulations!"

Happy Birthday! 
↓
★お誕生日おめでとうございます。
=Otanjoubi omedetou gozaimasu. (polite)

★お誕生日おめでとう!
=Otanjoubi omedetou! (For your friends.)

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Ex.25歳の誕生日、心からおめでとう!
=Nijuu go sai no tanjoubi kokoro kara omdetou!
Best wishes for your 25th birthday! 


Ex. 素敵な誕生日になります様に。
=Sutekina tanjoubi ni narimasu you ni.
=Wishing you a wonderful birthday! 

Ex. 楽しい誕生日を過ごしてね。
=Tanoshii tanjoubi wo sugoshite ne. (casual)
=Have a fun birthday today!

(Note : ね ending is usually for girls.)

Ex.これからもずっと素敵な(name) でいて下さい。
Korekara mo zutto sutekina + name + de ite kudasai.
Please stay wonderful (as you are).


Ex.今年も+name+にとって素晴らしい年であります様に!
=Kotoshi mo + name+ ni totte subarashii toshi de arimasu you ni!
=I hope the following year will bring you another wonderful one.

Ex. いつも友達でいてくれてありがとう!
=Itsumo tomodachi de ite kurete arigatou!
=Thank you always being my friend! 

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From Maggie sensei
みんなの誕生日はいつ?
Minna no tanjoubi wa itsu?
When is your birthday?