Translation guide
The English word 'whichever' is used to refer to any one of a limited set of options, or to say that it doesn't matter which one. In Japanese, this concept is expressed through several different structures depending on whether you are offering a choice, describing a free selection, or emphasizing that any option is fine.
Expressing that any one of a specific set of options is acceptable, or that the choice doesn't matter.
Used when choosing between two items. Literally 'either is fine'. Very common and natural.
どちらでもいいです。
Whichever is fine.
どちらでも好きな方を選んでください。
Please choose whichever you like.
Used when choosing among three or more items. 'Any one is fine'.
どれでも好きなのを取って。
Take whichever you like.
どれでも構いません。
Whichever is fine. (polite)
Casual version of どちらでも, used in spoken Japanese for two options.
どっちでもいいよ。
Whichever is fine. (casual)
Formal/literary equivalent of どれでも or どちらでも. Used in writing or formal speech.
いずれでも結構です。
Whichever is fine. (formal)
Emphasizing that the result is the same regardless of the choice.
'Whichever way it is' or 'either way'. Used when the outcome doesn't change based on the choice.
どちらにしても、結果は同じだ。
Whichever it is, the result is the same.
For three or more options. 'No matter which one'.
どれにしても大差ない。
Whichever one it is, there's not much difference.
Casual version of どちらにしても.
どっちにしても、僕は行かない。
Whichever it is, I'm not going.
Referring to a specific but unknown item from a set, often followed by a noun.
Used before a noun to mean 'whichever [noun]'. どちら is for two items.
どちらの案でも採用できます。
We can adopt whichever proposal.
For three or more items. 'Whichever [noun]'.
どの本でも借りられます。
You can borrow whichever book.
Formal version of どの〜でも or どちらの〜でも.
いずれの方法でも問題ありません。
Whichever method is fine.
Use どちらでも for two options (polite/neutral), どっちでも for two options (casual), and どれでも for three or more options. どちら is the polite form of どっち, but both are common in everyday speech depending on formality.
English 'whichever' often corresponds to these question-word + でも patterns. Do not try to translate 'whichever' as a single word; it will sound unnatural.