Translation guide
The English word 'someday' refers to an unspecified time in the future. In Japanese, the most common equivalent is いつか, but other expressions exist depending on nuance, such as 将来 (in the future) or そのうち (eventually).
Expressing that something will happen at some point in the future, without specifying when.
Referring to a time far in the future, often with a sense of uncertainty or hope.
Literally 'distant future'. Used when talking about something that may happen far ahead.
いつか is a neutral 'someday' that can be used for any future event. そのうち implies a more passive expectation that something will happen naturally, often without effort. For example, いつか勉強します (I will study someday) suggests a personal intention, while そのうちわかる (You'll understand eventually) suggests that understanding will come with time.
Someday I'll be rich.
I want to go to Japan someday.
Let's meet again someday.
Means 'in the future' and is more formal or abstract. Often used when talking about long-term plans or career goals.
Someday I want to become a doctor.
Means 'eventually' or 'sooner or later'. Implies that something will happen naturally over time, without a specific plan.
It will stop raining someday.
A more poetic or emphatic version of いつか. Often used in songs, literature, or emotional statements.
I believe that someday my dream will come true.
Someday in the distant future, humans may live on Mars.
A colloquial phrase meaning 'I don't know when, but...'. Used to express a vague intention for the future.
I don't know when, but someday I'd like to work abroad.
You'll understand eventually.
ある日 means 'one day' in the past, as in 'One day, a stranger appeared.' Do not use it for future 'someday'. For future, use いつか.
We'll meet again someday.