Date and time notation in South Korea

The most formal manner of expressing the full date and/or time in South Korea is to suffix each of the year, month, day, ante/post-meridiem indicator, hour, minute and second (in this order, i.e. with larger units first) with the corresponding unit and separating each with a space:[1] For example, the ISO 8601 timestamp 1975-07-14 09:18:32 would be written as “1975년 7월 14일 오전 9시 18분 32초”.

The national standard (KS X ISO8601, formerly KSX1511) also recognizes the ISO-8601-compliant date/time format of YYYY-MM-DD HH:MM:SS, which is widely used in computing and on the Korean internet.

12-hour clock is predominantly used in informal daily life, and the ante/post-meridiem indicator is often omitted where doing so does not introduce ambiguity.

When the time is expressed in the HH:MM:SS notation, the Roman ante/post-meridiem indicators (AM and PM) are also used frequently.

Examples include railway timetables, plane departure and landing timings, and TV schedules.