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15:30 in 12-Hour Time
15:30 is 3:30 PM.
Written 1530 in military time and said “fifteen thirty”. Going the other way, 3:30 PM is 15:30.
The 15:00 hour is the school pickup hour, and kick-off time for a great many afternoon fixtures.
24-hour clock
15:30
12-hour clock
3:30 PM
Said aloud: “fifteen thirty” on the 24-hour clock, “half past three in the afternoon” on the 12-hour one.
Why 15:30 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: 15 − 12 = 3, so 15:xx is 3: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 15:30 is in the afternoon, which is the information the AM/PM label is carrying.
Need this time to actually do something? Set an alarm for 3:30 PM, or use the timer to count a length of time instead of waiting for a clock time.
Common questions
What is 15:30 in 12-hour time?
15:30 is 3:30 PM. The minutes are unchanged; the hour is 15 − 12 = 3, and it takes PM.
What is 3:30 PM in 24-hour time?
3:30 PM is 15:30, written 1530 in military time.
How do you say 1530 out loud?
In military time it is said "fifteen thirty". On a 12-hour clock the same moment is "half past three in the afternoon".