Translation guide
Expresses mild obligation, advisability, or expectation. In Japanese, this is most naturally conveyed through conditional forms, the suffix 〜べき, or constructions like 〜ほうがいい, depending on the nuance.
Expressing that something is the right or proper thing to do, often based on social norms or personal principles.
The most direct equivalent of 'ought to' for moral or logical obligation. Attaches to the dictionary form of verbs. 〜べき is a noun-like suffix, so it can be followed by だ/です or other structures.
約束は守るべきだ。
You ought to keep your promises.
もっと勉強するべきです。
You ought to study more.
Common in spoken Japanese for giving advice or suggesting what someone ought to do. Literally 'it's better to do ~'. Softer than 〜べきだ.
早く寝たほうがいいよ。
You ought to go to bed early.
謝ったほうがいいと思います。
I think you ought to apologize.
Expresses that something must be done, often with a sense of necessity. Stronger than 'ought to' but used in similar contexts when the obligation is clear.
そろそろ行かないといけない。
I ought to be going soon.
Suggesting a course of action that is wise or beneficial, often based on the speaker's opinion.
A polite way to make a suggestion. Literally 'how about if you do ~?'. Often used when the speaker thinks the listener ought to do something.
医者に相談したらどうですか。
You ought to consult a doctor.
Expresses that someone ought to do something but isn't, often with a sense of regret or frustration. Used in casual speech.
もっと早く来ればいいのに。
You ought to come earlier (but you don't).
Indicating that something is likely to happen or should be the case based on logic or experience.
Used when the speaker expects something to be true or happen. 'Ought to' in the sense of 'should be the case'.
彼はもう着いているはずだ。
He ought to have arrived by now.
その薬を飲めば治るはずです。
If you take that medicine, you ought to get better.
Indicates a logical conclusion. 'That's why...' or 'it ought to be that...'. More explanatory than 〜はずだ.
彼は日本に10年住んでいたから、日本語が上手なわけだ。
He lived in Japan for 10 years, so his Japanese ought to be good.
べきだ expresses a stronger sense of moral duty or social obligation, while ほうがいい is a softer, more personal recommendation. Use べきだ for rules and principles, and ほうがいい for friendly advice.
法律は守るべきだ。
You ought to obey the law.
傘を持っていったほうがいいよ。
You ought to take an umbrella.
There is no single Japanese word that directly translates 'ought to'. Using べき in every case can sound overly formal or preachy. Choose the pattern that matches the nuance: obligation, advice, or expectation.
医者に診てもらったほうがいいですよ。
You ought to see a doctor.
もう出発したほうがいい。
We ought to leave now.
それで十分なはずだ。
That ought to be enough.