Translation guide
The English verb 'fail' covers a wide range of meanings, from not succeeding to not doing something expected. Japanese uses different verbs and patterns depending on the nuance.
To not achieve a desired outcome; to be unsuccessful in an attempt.
The most common and general way to say 'fail' when an action or plan does not succeed.
試験に失敗した。
I failed the exam.
計画は失敗に終わった。
The plan ended in failure.
Specifically means to fail an exam or test. Very common in academic contexts.
数学のテストに落ちた。
I failed the math test.
Formal way to say 'fail' an exam or screening. Often used in official announcements.
面接で不合格になった。
I failed the interview.
Colloquial and somewhat rough way to say 'mess up' or 'fail'. Used among friends.
またしくじっちゃった。
I messed up again.
To neglect or be unable to do something that was expected or required.
Attach to the stem of a verb to mean 'fail to do' or 'miss the chance to do'. Emphasizes missing an opportunity or not completing an action.
電車に乗り損なった。
I failed to catch the train.
言い損なってしまった。
I failed to say it.
Means 'forget to do' and implies failure due to forgetting.
宿題をするのを忘れた。
I forgot to do my homework. (I failed to do it.)
Simply means 'cannot do'. Often used when capability is lacking, leading to failure.
約束を守れなかった。
I failed to keep my promise.
For a machine, system, or body part to stop functioning properly.
General term for mechanical or electronic failure.
エンジンが故障した。
The engine failed.
Means 'break' or 'be broken'. More general than 故障する, used for non-mechanical things too.
パソコンが壊れた。
My computer failed / broke.
Colloquial for 'go bad', 'become useless', or 'fail'. Can refer to food, plans, or things.
冷蔵庫がダメになった。
The fridge failed / gave out.
To not meet expectations; to let someone down.
Literally 'cannot meet expectations'. A natural way to express failing someone.
彼は親の期待に応えられなかった。
He failed to live up to his parents' expectations.
Means 'betray'. Stronger than just disappointing; implies a breach of trust.
彼は私の信頼を裏切った。
He failed me / betrayed my trust.
For health, strength, or a faculty to deteriorate.
To decline, weaken, or fail (e.g., health, eyesight, memory).
年をとると記憶力が衰える。
As you get older, your memory fails.
To weaken, become frail. Often used for physical condition.
For a business to fail financially.
Standard term for corporate bankruptcy.
その会社は倒産した。
The company failed / went bankrupt.
Colloquial for a business going under.
あの店、潰れたんだって。
I heard that shop failed / went out of business.
While 失敗する is the most direct equivalent, it is not used for all senses of 'fail'. For exams, 落ちる is more natural; for forgetting, use 忘れる; for machines, use 故障する. Using 失敗する in these contexts can sound unnatural.
失敗する is neutral and can be used in any situation. しくじる is slangy and implies a blunder, often used when you mess up something you should have handled well. Avoid しくじる in formal settings.
彼は必ず母親に電話する。
He never fails to call his mother.
English 'never fails to' is often expressed with 必ず (without fail) or 忘れずに.
His heart is failing.