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13:00 in 12-Hour Time

13:00 is 1:00 PM.

Written 1300 in military time and said “thirteen hundred hours”. Going the other way, 1:00 PM is 13:00.

The 13:00 hour is the first hour that actually changes when you convert — the one that makes the 24-hour clock look unfamiliar.

24-hour clock

13:00

12-hour clock

1:00 PM

Said aloud: “thirteen hundred hours” on the 24-hour clock, “one o'clock in the afternoon” on the 12-hour one.

1:00 PM

Why 13:00 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: 13 − 12 = 1, so 13:xx is 1:xx PM. Going the other way, add 12 to any PM hour except 12 PM itself.

The minutes are the same on both clocks — a whole hour stays a whole hour — and 13:00 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 1:00 PM, or use the timer to count a length of time instead of waiting for a clock time.

Nearby times

Common questions

What is 13:00 in 12-hour time?
13:00 is 1:00 PM. The minutes are unchanged; the hour is 13 − 12 = 1, and it takes PM.

What is 1:00 PM in 24-hour time?
1:00 PM is 13:00, written 1300 in military time.

How do you say 1300 out loud?
In military time it is said "thirteen hundred hours". On a 12-hour clock the same moment is "one o'clock in the afternoon".

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