Time Duration Calculator
Find the time between a start and an end clock time, including overnight shifts.
Example · 10:30 PM → 6:15 AM next day = 7h 45m
Military Time Converter
Convert between 12-hour and 24-hour (military) time.
Your entries stay in this browser
Midnight is 0000 and noon is 1200. 2400 is not accepted. See calculation methodology
How to use it
- Input
- 2:35 PM
- Rule
- PM adds 12 hours to hours 1–11
- Result
- 1435 · 14:35
- Input
- 0030
- Rule
- Hour 00 is 12 AM
- Result
- 12:30 AM
- Choose 12-hour to 24-hour, or 24-hour to 12-hour.
- Enter the time.
- Select Convert.
- Copy the result, or use “Swap direction” to convert it back.
How it works
Military time counts hours from 00 to 23 and always uses four digits, so 7:05 AM is 0705.
12:00 AM (midnight) is 0000 and 12:00 PM (noon) is 1200. This converter does not accept 2400: midnight is always 0000.
12 AM → hour 00 · 12 PM → hour 12
1–11 AM → same hour · 1–11 PM → hour + 12Note. Midnight is 0000 and noon is 1200. 2400 is not accepted.
12-hour and 24-hour reference
| 12-hour | 24-hour |
|---|---|
| 12:00 AM | 0000 |
| 1:00 AM | 0100 |
| 6:30 AM | 0630 |
| 12:00 PM | 1200 |
| 1:00 PM | 1300 |
| 6:30 PM | 1830 |
| 9:45 PM | 2145 |
| 11:59 PM | 2359 |
Frequently asked questions
Is midnight 0000 or 2400?
HourCalio uses 0000 for midnight at the start of the day. The converter rejects 2400, so each time has one spelling.
What is 12:00 PM in military time?
Noon, 1200. 12:00 AM is midnight, 0000.
Do I need leading zeros?
Military time always has four digits, so 9:05 AM is 0905. When you enter a 24-hour time here, 905 and 9:05 are also accepted.