Translation guide
The English phrase 'on time' refers to punctuality—arriving or happening at the scheduled or expected time. In Japanese, this concept is expressed through various adverbs, adjectives, and set phrases, depending on the context and level of formality.
The train came on time.
The meeting started on time.
Formal term often used for transportation schedules (trains, planes) or official events. Implies strict adherence to a timetable.
The plane departed on time.
Literally 'without being late'. Used as an adverb, often in instructions or expectations. Slightly more casual than 時間通りに.
Please come on time.
A noun meaning 'punctuality' or 'strict adherence to time'. Often seen on invitations or schedules as a request to be punctual.
Please be punctual (strictly on time).
Indicating that something will happen at the appropriate time, not necessarily immediately.
Arriving or happening exactly at the required moment, often narrowly avoiding lateness.
Means 'just barely on time' or 'at the last minute'. Conveys a sense of narrow escape from being late.
I caught the train just in time.
Literally 'by a hair's breadth'. Emphasizes a very close call, often used in dramatic situations.
I made it just in the nick of time.
時間通りに is the everyday expression for 'on time' and can be used in most situations. 定刻に is more formal and is typically used for scheduled transport or official events. Using 定刻に in casual conversation may sound stiff.
The bus came on time. (casual)
The bus arrived on schedule. (formal announcement)
Do not translate 'on time' word-for-word as 時間の上に or similar. The natural Japanese expressions are idiomatic and must be learned as set phrases.
The rain will stop in time.