Translation guide
Expresses that an action or state continues throughout the entire day. Japanese uses various time expressions, adverbs, and phrases depending on nuance.
To say that something lasts or happens for the whole day, from morning to night.
The most common and natural way to say 'all day'. Used for continuous actions or states.
昨日は一日中雨が降っていた。
It rained all day yesterday.
彼は一日中ゲームをしている。
He plays games all day.
Can mean 'all day' in certain contexts, especially with verbs like 過ごす (spend) or when emphasizing the whole day as a unit. Often used with まるまる (entire) for emphasis.
Without context, 一日 simply means 'one day'. To clearly mean 'all day', use 一日中 or add まるまる.
まるまる一日を勉強に費やした。
I spent the entire day studying.
一日中と一日は少し違います。
'Ichinichijuu' and 'ichinichi' are slightly different.
Formal, often used in written language or official announcements.
本日は終日営業しております。
We are open all day today.
Describing services, shops, or availability that lasts the whole day.
Works for availability as well.
このカフェは一日中開いています。
This cafe is open all day.
Common in business contexts.
Emphasizing that something continues without stopping from morning to night.
Literally 'from morning to night', very natural for emphasizing the whole day.
朝から晩まで働いた。
I worked all day long.
Adds ずっと (continuously) to 一日中 for extra emphasis.
彼女は一日中ずっと泣いていた。
She was crying all day long.
Sometimes 'all day' can mean 'every day' in phrases like 'I could do this all day'.
Means 'every day'. Use when 'all day' implies a habitual action.
This is not a direct translation of 'all day' but captures the meaning in such contexts.
毎日これが食べられる。
I could eat this all day.
一日中 (いちにちじゅう) specifically means 'all day long' or 'throughout the day'. 一日 (いちにち) simply means 'one day' or 'a day'. To express 'all day', 一日中 is the safest choice. 一日 can work with modifiers like まるまる (entire) or in set phrases.
Avoid directly translating 'all day' as すべての日 (subete no hi) or 全部の日 (zenbu no hi). These are unnatural. Use the expressions above.
終日無料駐車場あり。
Free parking all day.