Translation guide
The English phrase 'be careful' is used to warn someone about potential danger, to advise caution in handling something, or to express concern for someone's well-being. In Japanese, the appropriate expression depends on the situation: whether you are warning of immediate danger, giving general advice, or saying goodbye.
Be careful! (warning of danger)
Be careful. (general advice)
Take care! (when saying goodbye)
To alert someone to a sudden or imminent danger, like 'Watch out!' or 'Look out!'
Literally 'dangerous', this is the most common and natural way to shout a warning when someone is about to get hurt or something bad is about to happen.
Watch out! A car is coming!
Literally 'attach your mind/energy', this is a general 'be careful' used for both immediate and general caution. In urgent situations, it is less sharp than 危ない.
To advise someone to be cautious in a non-urgent situation, such as handling something fragile, crossing the street, or dealing with a tricky person.
To express 'take care' or 'stay safe' when parting, often implying a journey or a period of separation.
The standard way to say 'take care' when someone is leaving. It can be used alone or with other farewells.
To advise someone to pay close attention to detail, avoid mistakes, or be meticulous in a task.
気をつける is the most common and versatile. 注意する is more formal and often used in written warnings or official announcements. 用心する implies being on guard against potential harm or bad intentions, similar to 'beware'.
Be careful on the stairs. (casual)
Be careful not to catch a cold.
Be careful! There's a rock by your feet.
The most versatile and common way to say 'be careful' in Japanese. Can be used in many contexts, from everyday safety to social caution.
Please be careful when carrying the glass.
He's a liar, so you'd better be careful.
More formal than 気をつける, often used in written warnings, announcements, or when giving official caution. Can also mean 'to warn someone'.
Please watch your step.
Implies being on guard against potential danger or bad people, like 'beware' or 'be vigilant'. Often used for crime prevention.
Please be careful on the streets at night.
Well then, take care on your way home.
A politer version of 気をつけて, adding the honorific prefix お. Suitable for saying goodbye to superiors or customers.
Please take care on your way home. (polite)
A formal and somewhat old-fashioned way to wish someone a safe journey or safe return, literally 'in safety'. Used in letters or formal speeches.
Please take care of yourself. (formal)
Still the most common phrase, but often combined with specific verbs or nouns to indicate what to be careful about.
Please be careful about the stroke order of the kanji.
Literally 'pay attention', this is more formal and emphasizes focused attention. Often used in business or academic contexts.
Please work while paying attention to the details.
階段に注意してください。
Please be careful on the stairs. (formal/written)
Beware of pickpockets.
注意する is not used as a farewell. Saying 注意してください when someone leaves sounds like you are warning them about something specific, not wishing them well. Use 気をつけて or お気をつけて instead.
彼に言うことには気をつけたほうがいいよ。
Be careful what you say to him.
Be careful! The floor is slippery.