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16:30 in 12-Hour Time
16:30 is 4:30 PM.
Written 1630 in military time and said “sixteen thirty”. Going the other way, 4:30 PM is 16:30.
The 16:00 hour is late afternoon, when shift handovers and end-of-day deadlines are written.
24-hour clock
16:30
12-hour clock
4:30 PM
Said aloud: “sixteen thirty” on the 24-hour clock, “half past four in the afternoon” on the 12-hour one.
Why 16:30 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: 16 − 12 = 4, so 16:xx is 4: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 16:30 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 4:30 PM, or use the timer to count a length of time instead of waiting for a clock time.
Common questions
What is 16:30 in 12-hour time?
16:30 is 4:30 PM. The minutes are unchanged; the hour is 16 − 12 = 4, and it takes PM.
What is 4:30 PM in 24-hour time?
4:30 PM is 16:30, written 1630 in military time.
How do you say 1630 out loud?
In military time it is said "sixteen thirty". On a 12-hour clock the same moment is "half past four in the afternoon".