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TimeAndSpace.Science

00:30 in 12-Hour Time

00:30 is 12:30 AM.

Written 0030 in military time and said “zero zero thirty”. Going the other way, 12:30 AM is 00:30.

The 00:00 hour is the start of the day on every 24-hour clock, and the one that catches people out: it is 12 AM, not 12 PM. Timetables and hospital charts write the date change here.

24-hour clock

00:30

12-hour clock

12:30 AM

Said aloud: “zero zero thirty” on the 24-hour clock, “half past twelve at night” on the 12-hour one.

12:30 AM

Why 00:30 converts the way it does

Midnight is the first of the two times people get wrong. On the 24-hour clock the day starts at 00:00; on the 12-hour clock the same moment is 12:00 AM — twelve, and AM. It is never 12 PM, and 24:00 is the same instant written as the END of the previous day, which is why a timetable will show a service departing at 00:10 on Tuesday and never at 24:10 on Monday.

The minutes are the same on both clocks — the :30 never moves — and 00:30 is at night, which is the information the AM/PM label is carrying.

Need this time to actually do something? Set an alarm for 12:30 AM, or use the timer to count a length of time instead of waiting for a clock time.

Nearby times

Common questions

What is 00:30 in 12-hour time?
00:30 is 12:30 AM. The minutes are unchanged; the hour 00 becomes 12 and takes AM, because 00:00 is midnight.

What is 12:30 AM in 24-hour time?
12:30 AM is 00:30, written 0030 in military time.

How do you say 0030 out loud?
In military time it is said "zero zero thirty". On a 12-hour clock the same moment is "half past twelve at night".

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