Dictionary / Japanese / Dad
How to Say "Dad" in Japanese
お父さん
otōsan
Literally: (Respected) father
お
(polite prefix)
父
father
さん
(polite title)
Polite or casual
Politeお父様 (otōsama)
Casualパパ (papa) / 父さん (tōsan)
お父さん is the everyday word for dad. You use it to call your own father, and to talk about someone else's father. When you mention your own father in polite conversation, for example to a teacher, a boss or someone you have just met, say 父 (chichi). Your family counts as your own side, so you do not use polite words for them in front of outsiders. パパ (papa) is common with small children. お父様 (otōsama) is a very polite way to refer to someone else's father.
Correct
お父さん
What people say wrong
親父
My old man. Very casual, out of place in polite conversation.
The mistake to avoid. Anime and manga often use 親父 (oyaji), my old man. It is real, but very casual, and you hear it mostly from men talking about their own father. Avoid it with anyone you speak politely to. The other trap is the same as with mom: to outsiders, your own father is 父, and their father is お父さん. In hiragana it is おとうさん. The う makes a long o, so say otōsan, not otosan.
In context
お父さん、おかえり。
Otōsan, okaeri.
Welcome home, Dad.
父は会社員です。
Chichi wa kaishain desu.
My father works for a company. (to someone outside the family)
お父さんはお元気ですか。
Otōsan wa ogenki desu ka.
How is your father?