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:
For example, the ISO 8601 timestamp 1975-07-14 09:18:32 would be written as âÂÂâÂÂ.
The same rules apply when expressing the date or the time alone, e.g., âÂÂâÂÂ, âÂÂâÂÂ, âÂÂâÂÂ, âÂÂâ and âÂÂâÂÂ.
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.
In written documents, the date form above (but not the time) is often abbreviated by replacing each unit suffix with a single period; for example, would be abbreviated as âÂÂâ (note the trailing period and intervening spaces as this is of importance).
Both the 12-hour and 24-hour notations are widely used in South Korea.
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.
Half past the hour is commonlyâÂÂespecially in spoken KoreanâÂÂabbreviated as , which literally means âÂÂhalfâÂÂ; for example, 13:30 is either expressed as âÂÂâ or âÂÂâÂÂ.
When the time is expressed in the HH:MM:SS notation, the Roman ante/post-meridiem indicators (AM and PM) are also used frequently. In addition, they sometimes follow the convention of writing the Korean-style indicator before the time; it is not uncommon to encounter times expressed in such a way, e.g., âÂÂâ instead of âÂÂâÂÂ.
Two words, and , are sometimes used to indicate 12:00 and 0:00 respectivelyâÂÂmuch in the same way the English words noon and midnight are used.
The 24-hour notation is more commonly used in text and is written "" or "". Examples include railway timetables, plane departure and landing timings, and TV schedules. In movie theaters it is also not uncommon to see something like 25:30 for the 01:30 AM movie.