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12-Hour and 24-Hour Clock Converter
Set either clock and read the other. 14:30 is 2:30 PM, 9:45 PM is 21:45 — the minutes never move, only the hour and the AM/PM label.
24-hour clock
14:30
12-hour clock
2:30 PM
Said aloud: “fourteen thirty” on the 24-hour clock, “half past two in the afternoon” on the 12-hour one.
How to convert, in your head
24-hour → 12-hour. Hours 13–23: subtract 12 and add PM (17:20 → 5:20 PM). Hours 01–11: keep the hour, add AM (08:05 → 8:05 AM). 12:00 is 12:00 PM. 00:00 is 12:00 AM.
12-hour → 24-hour. PM times from 1 to 11: add 12 (6:40 PM → 18:40). AM times: keep the hour and pad it to two digits (7:05 AM → 07:05). 12:00 PM stays 12:00. 12:00 AM becomes 00:00.
The two that catch everyone. Midnight and noon are the only hours that do not simply gain or lose twelve. 12 AM is 00:00 and 12 PM is 12:00. If a page, a form or a colleague says "12 PM tonight", it is worth asking which one they mean — the 24-hour clock exists precisely so that question never has to be asked.
Military time is this same 24-hour clock with the colon dropped and the digits spoken: 14:30 is written 1430 and said “fourteen thirty”; 07:00 is 0700, “zero seven hundred hours”.
24-hour clock chart
Every hour, both ways. The right-hand column is the left-hand column plus twelve — that is the whole conversion.
| 24-hour | 12-hour | Said as |
|---|---|---|
| 00:00 | 12:00 AM | zero zero hundred hours |
| 01:00 | 1:00 AM | zero one hundred hours |
| 02:00 | 2:00 AM | zero two hundred hours |
| 03:00 | 3:00 AM | zero three hundred hours |
| 04:00 | 4:00 AM | zero four hundred hours |
| 05:00 | 5:00 AM | zero five hundred hours |
| 06:00 | 6:00 AM | zero six hundred hours |
| 07:00 | 7:00 AM | zero seven hundred hours |
| 08:00 | 8:00 AM | zero eight hundred hours |
| 09:00 | 9:00 AM | zero nine hundred hours |
| 10:00 | 10:00 AM | ten hundred hours |
| 11:00 | 11:00 AM | eleven hundred hours |
| 24-hour | 12-hour | Said as |
|---|---|---|
| 12:00 | 12:00 PM | twelve hundred hours |
| 13:00 | 1:00 PM | thirteen hundred hours |
| 14:00 | 2:00 PM | fourteen hundred hours |
| 15:00 | 3:00 PM | fifteen hundred hours |
| 16:00 | 4:00 PM | sixteen hundred hours |
| 17:00 | 5:00 PM | seventeen hundred hours |
| 18:00 | 6:00 PM | eighteen hundred hours |
| 19:00 | 7:00 PM | nineteen hundred hours |
| 20:00 | 8:00 PM | twenty hundred hours |
| 21:00 | 9:00 PM | twenty-one hundred hours |
| 22:00 | 10:00 PM | twenty-two hundred hours |
| 23:00 | 11:00 PM | twenty-three hundred hours |
Convert a specific time
Every half hour has its own page, with the answer, how it is said aloud, and an alarm you can set for it.
Common questions
How do you convert 24-hour time to 12-hour time?
For hours 13 through 23, subtract 12 and add PM: 14:30 becomes 2:30 PM. Hours 01 through 11 keep their number and take AM. 12:00 is 12:00 PM (noon) and 00:00 is 12:00 AM (midnight). The minutes never change.
How do you convert 12-hour time to 24-hour time?
For PM times from 1 PM to 11 PM, add 12: 9:45 PM becomes 21:45. AM times keep their hour and take a leading zero where needed: 7:05 AM becomes 07:05. 12:00 PM stays 12:00, and 12:00 AM becomes 00:00.
Is military time the same as the 24-hour clock?
Almost. Military time is the 24-hour clock written without the colon and usually spoken digit by digit — 14:30 is written 1430 and said "fourteen thirty". A whole hour takes "hundred hours": 07:00 is 0700, said "zero seven hundred hours". The arithmetic is identical.
What is 12 AM and 12 PM in 24-hour time?
12 AM is midnight, 00:00 — the start of the day. 12 PM is noon, 12:00. These are the only two conversions that surprise people, because 12 is the one hour that does not simply gain or lose twelve.
Is there a 24:00, and what about 00:00?
Both exist and mean the same instant. 00:00 is midnight at the start of a day and 24:00 is midnight at its end, so 24:00 on Monday and 00:00 on Tuesday are the same moment. Clocks and timetables use 00:00; 24:00 appears mainly as an end boundary, as in "open 00:00–24:00".
Which countries use the 24-hour clock?
Most of the world uses it in writing — across Europe, Latin America and Asia — while the United States, Canada (outside Quebec), Australia, New Zealand and the Philippines mainly speak and write the 12-hour clock. Even there, the 24-hour clock is standard in aviation, the military, medicine, computing and public transport, because it cannot be misread.