Translation guide
The English word "certainly" is used to express strong agreement, polite willingness, or absolute certainty. In Japanese, the best translation depends on the context: whether you are agreeing to a request, confirming a fact, or emphasizing that something is definitely true.
Use when you want to say 'yes, I will do that' or 'of course' in a polite way, often in service or formal situations.
Very polite, used especially in customer service. Literally 'I have understood (humbly)'. It conveys that you will certainly carry out the request.
"Water, please." "Certainly."
Formal, often used in business. Means 'I understand and will comply'. Slightly less humble than かしこまりました but still very polite.
"Please submit the documents by tomorrow." "Certainly."
Polite and common. Means 'of course'. Suitable for many situations, but slightly less formal than the above.
"Can you help me?" "Certainly."
Casual and friendly. Means 'Sure, it's fine'. Use only with friends or in informal settings. Not suitable for formal requests.
"Lend me a pen." "Certainly."
Use when you want to stress that a statement is undoubtedly correct, often in response to doubt or to add conviction.
Means 'certainly' or 'indeed'. Used to confirm that something is true based on evidence or personal knowledge. Often used at the beginning of a sentence.
He is certainly an excellent engineer.
"This restaurant is expensive, isn't it?" "It certainly is."
Literally 'without mistake'. Stronger than 確かに. Emphasizes that there is no doubt. Can sound a bit emphatic.
He will certainly come.
Means 'without fail' or 'definitely'. Often used for promises or rules. Implies a strong obligation or inevitability.
Formal/literary. Means 'needless to say' or 'certainly'. Used to introduce an obvious fact.
Use when someone asks if they can do something and you want to say 'certainly, go ahead'.
Use when you are sure something will happen.
These three words all translate to 'certainly' but have different nuances. 確かに (tashika ni) is used when confirming a fact based on evidence ('indeed'). きっと (kitto) expresses a strong belief or hope about the future ('surely'). 必ず (kanarazu) implies an absolute rule or promise ('without fail').
While もちろん (mochiron) can mean 'certainly', it is often used as 'of course'. In very formal situations, かしこまりました or 承知しました are more appropriate. Using もちろん with superiors might sound presumptuous.
必ず成功する。
You will certainly succeed.
Certainly, health is important.
"May I sit here?" "Certainly, I don't mind."
彼は必ず戻ってくる。
He will certainly come back.