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23:30 in 12-Hour Time
23:30 is 11:30 PM.
Written 2330 in military time and said “twenty-three thirty”. Going the other way, 11:30 PM is 23:30.
The 23:00 hour is the last hour of the day — 23:59 is the deadline every system means when it says 'end of day'.
24-hour clock
23:30
12-hour clock
11:30 PM
Said aloud: “twenty-three thirty” on the 24-hour clock, “half past eleven at night” on the 12-hour one.
Why 23:30 converts the way it does
This is the half of the day that actually changes. From 13:00 to 23:00, subtract 12 to get the 12-hour hour and label it PM: 23 − 12 = 11, so 23:xx is 11:xx PM. Going the other way, add 12 to any PM hour except 12 PM itself.
The minutes are the same on both clocks — the :30 never moves — and 23:30 is at night, which is the information the AM/PM label is carrying.
Need this time to actually do something? Set an alarm for 11:30 PM, or use the timer to count a length of time instead of waiting for a clock time.
Common questions
What is 23:30 in 12-hour time?
23:30 is 11:30 PM. The minutes are unchanged; the hour is 23 − 12 = 11, and it takes PM.
What is 11:30 PM in 24-hour time?
11:30 PM is 23:30, written 2330 in military time.
How do you say 2330 out loud?
In military time it is said "twenty-three thirty". On a 12-hour clock the same moment is "half past eleven at night".