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22:30 in 12-Hour Time
22:30 is 10:30 PM.
Written 2230 in military time and said “twenty-two thirty”. Going the other way, 10:30 PM is 22:30.
The 22:00 hour is the start of the night shift, and a common departure time for red-eye flights.
24-hour clock
22:30
12-hour clock
10:30 PM
Said aloud: “twenty-two thirty” on the 24-hour clock, “half past ten at night” on the 12-hour one.
Why 22:30 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: 22 − 12 = 10, so 22:xx is 10: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 22:30 is at night, which is the information the AM/PM label is carrying.
Need this time to actually do something? Set an alarm for 10:30 PM, or use the timer to count a length of time instead of waiting for a clock time.
Common questions
What is 22:30 in 12-hour time?
22:30 is 10:30 PM. The minutes are unchanged; the hour is 22 − 12 = 10, and it takes PM.
What is 10:30 PM in 24-hour time?
10:30 PM is 22:30, written 2230 in military time.
How do you say 2230 out loud?
In military time it is said "twenty-two thirty". On a 12-hour clock the same moment is "half past ten at night".