Translation guide
How to express that something is not known, unfamiliar, or unidentified in Japanese.
Expressing that a fact, person, place, or thing is not known or familiar.
The most common way to say 'I don't know' about a fact or piece of information. Casual.
そのことは知らない。
I don't know about that.
彼がどこにいるか知らない。
I don't know where he is.
Polite form of 知らない. Use in formal situations or with strangers.
すみません、知りません。
Sorry, I don't know.
Literally 'I don't understand', but often used like 'I don't know' when the answer isn't clear or you haven't figured it out.
答えが分からない。
I don't know the answer.
Formal/written term meaning 'unknown' or 'unidentified'. Often used in reports or news.
原因は不明です。
The cause is unknown.
Describing something whose identity, name, or nature is not known.
Used for mysterious objects, creatures, or people whose true identity is unknown.
正体不明の生物が発見された。
An unidentified creature was discovered.
Specifically for a person whose identity (name, background) is unknown, e.g., a John Doe.
Means 'unknown' in the sense of not yet discovered or explored. Often used in science or exploration.
未知のウイルス
an unknown virus
Describing a person, place, or thing that is not well-known or recognized.
Literally 'no name', meaning unknown or obscure. Often used for artists, writers, etc.
彼はまだ無名の画家だ。
He is still an unknown painter.
A phrase meaning 'not known' or 'not recognized'. More descriptive than 無名.
この町はあまり知られていない。
This town is not very well known.
While 不明 means 'unknown', it is formal and often used in written contexts. In everyday speech, use 知らない or 分からない instead.
そのことは不明です。
That is unknown. (overly formal for casual chat)
身元不明の遺体が見つかった。
An unidentified body was found.