Translation guide
How to express that something is done or happens without a reason, cause, or justification in Japanese.
Expressing that an action or feeling occurs spontaneously, without a specific cause or motive.
A very common, natural way to say 'without any particular reason' or 'just because'. It conveys a vague, intuitive feeling or action.
なんとなく外に出た。
I went outside without any particular reason.
なんとなく悲しい。
I feel sad for no reason.
Literally 'without even a reason'. More direct than なんとなく, and can sound slightly more emphatic or negative.
理由もなく彼は怒り出した。
He got angry without any reason.
Similar to 理由もなく, meaning 'without reason/cause'. Often used in more emotional or literary contexts.
わけもなく涙が出た。
Tears came to my eyes for no reason.
Indicating that an action, accusation, or belief lacks a valid basis or is unreasonable.
A straightforward way to say 'without reason', often used in formal or written contexts when stating that something is groundless.
理由なく欠席することは許されない。
Absence without reason is not permitted.
Means 'without justifiable reason'. Used in legal, official, or formal contexts.
正当な理由なく解雇された。
I was dismissed without just cause.
Literally 'without basis/grounds'. Used when criticizing unfounded claims or accusations.
根拠なく人を疑ってはいけない。
You shouldn't suspect people without grounds.
Describing a person, action, or situation that is not based on reason or logic.
Emphasizing that something happens completely without cause, often with a nuance of surprise or frustration.
Stronger than 理由もなく, meaning 'without any reason whatsoever'.
何の理由もなく彼は去った。
He left without any reason at all.
An adverb meaning 'without reason/cause', often used in set phrases like いわれなく非難される (to be criticized for no reason).
いわれなく非難された。
I was criticized without reason.
なんとなく is the most natural for everyday 'without reason' when describing vague feelings or casual actions. 理由もなく is more direct and can imply that a reason should exist but doesn't, sometimes carrying a negative tone.
なんとなくここに来た。
I came here just because.
理由もなく彼は私を避ける。
He avoids me for no reason.
Direct translations like '理由なしで' are not natural. Use the phrases provided. Also, note that 'without reason' in English can sometimes be expressed by a simple 'just because' in Japanese, which is captured by なんとなく.
That decision is irrational.