# What is it in military time?

Converts between 12-hour a.m./p.m. time and military (24-hour) time, adds or subtracts hours and minutes, and finds the time between two military times.

- Page: https://www.acalculator.org/days/military-time-calculator
- JSON spec: https://www.acalculator.org/days/military-time-calculator.json
- Version: dabf61626ba0

## Default answer

Example with the default inputs (I want to Convert standard time to military time, Standard time 14:30): 2:30 p.m. is 1430 in military time.

## Inputs

| Key | Label | Description |
| --- | --- | --- |
| mode | I want to | Convert either way, add or subtract time, or find the time between two military times. |
| t | Standard time | A clock time, such as 2:30 pm. |
| m | Military time | Four digits from 0000 to 2359, such as 0930 or 1745; a colon (17:45) is fine. |
| e | End military time | The later time, 0000 to 2400; one before the start time is read as the next day. |
| h | Hours to add | Whole hours; a negative number subtracts. |
| min | Minutes to add | Whole minutes; a negative number subtracts. |

## Outputs

| Key | Label | Description |
| --- | --- | --- |
| result | Answer | The military time, the standard time, or the time between, by mode. |
| military | Military time | Four digits, no colon: 0000 to 2359 (2400 ends a day). |
| standard | Standard time | The 12-hour clock with a.m. or p.m. |
| day | Day | Which day the result falls on, from the start time’s day. |
| totalMinutes | Total minutes | The time between, in minutes. |
| decimalHours | Decimal hours | The time between, in hours. |
| sentence | In words | The answer as a sentence. |

## Method

Military time = HHMM of the 24-hour clock; adding works in minutes after midnight, modulo 1,440, counting the days passed; an end time before the start is the next day.

## Assumptions

- Times are whole minutes. 0000 is midnight at the start of a day and 2400 midnight at its end; 2400 is accepted as an end time and when converting.
- 12:00 a.m. is midnight and 12:00 p.m. is noon; the page adds the words, because NIST calls the a.m./p.m. labels ambiguous.
- No time zones or daylight saving time changes.

## Worked examples

1. mode = to-military, t = 14:30 gives result = 1430, standard = 2:30 p.m.. Source: Wikipedia, 24-hour clock, Military time (four digits with no separator, 0000 to 2359; 12:00 a.m. = 0000, 12:00 p.m. = 1200, 1:00 p.m. = 1300; midnight as 0000 or 2400), https://en.wikipedia.org/wiki/24-hour_clock (retrieved 2026-10-02); NIST, Times of Day FAQs (12 a.m. and 12 p.m. are ambiguous; in 24-hour notation 0000 is midnight at the start of a day and 2400 the end of it), https://www.nist.gov/pml/time-and-frequency-division/times-day-faqs (retrieved 2026-10-02).
2. mode = to-military, t = 00:05 gives result = 0005, standard = 12:05 a.m.. Source: NIST, Times of Day FAQs (12 a.m. and 12 p.m. are ambiguous; in 24-hour notation 0000 is midnight at the start of a day and 2400 the end of it), https://www.nist.gov/pml/time-and-frequency-division/times-day-faqs (retrieved 2026-10-02).
3. mode = to-standard, m = 1200 gives result = 12:00 p.m. (noon). Source: NIST, Times of Day FAQs (12 a.m. and 12 p.m. are ambiguous; in 24-hour notation 0000 is midnight at the start of a day and 2400 the end of it), https://www.nist.gov/pml/time-and-frequency-division/times-day-faqs (retrieved 2026-10-02).
4. mode = to-standard, m = 2400 gives result = 12:00 a.m. (midnight, end of the day), military = 2400. Source: NIST, Times of Day FAQs (12 a.m. and 12 p.m. are ambiguous; in 24-hour notation 0000 is midnight at the start of a day and 2400 the end of it), https://www.nist.gov/pml/time-and-frequency-division/times-day-faqs (retrieved 2026-10-02).
5. mode = add, m = 1745, h = 8, min = 30 gives result = 0215, standard = 2:15 a.m., day = the next day. Source: Wikipedia, 24-hour clock, Military time (four digits with no separator, 0000 to 2359; 12:00 a.m. = 0000, 12:00 p.m. = 1200, 1:00 p.m. = 1300; midnight as 0000 or 2400), https://en.wikipedia.org/wiki/24-hour_clock (retrieved 2026-10-02).
6. mode = add, m = 0630, h = -10, min = 0 gives result = 2030, day = the day before. Source: Wikipedia, 24-hour clock, Military time (four digits with no separator, 0000 to 2359; 12:00 a.m. = 0000, 12:00 p.m. = 1200, 1:00 p.m. = 1300; midnight as 0000 or 2400), https://en.wikipedia.org/wiki/24-hour_clock (retrieved 2026-10-02).
7. mode = between, m = 1745, e = 0215 gives result = 8 hours 30 minutes, totalMinutes = 510, decimalHours = 8.5. Source: Wikipedia, 24-hour clock, Military time (four digits with no separator, 0000 to 2359; 12:00 a.m. = 0000, 12:00 p.m. = 1200, 1:00 p.m. = 1300; midnight as 0000 or 2400), https://en.wikipedia.org/wiki/24-hour_clock (retrieved 2026-10-02).
8. mode = between, m = 0000, e = 2400 gives result = 24 hours 0 minutes, totalMinutes = 1,440. Source: NIST, Times of Day FAQs (12 a.m. and 12 p.m. are ambiguous; in 24-hour notation 0000 is midnight at the start of a day and 2400 the end of it), https://www.nist.gov/pml/time-and-frequency-division/times-day-faqs (retrieved 2026-10-02).

## FAQ

### How do I convert to military time?

For a.m. times, write the hour with a leading zero: 9:15 a.m. is 0915. For p.m. times, add 12 to the hour: 2:30 p.m. is 1430. The two exceptions are 12:xx a.m., which becomes 00xx (12:05 a.m. is 0005), and 12:xx p.m., which stays 12xx.

### How do I convert military time to standard time?

For 0100 to 1159, add a.m. (0945 is 9:45 a.m.). For 1300 to 2359, subtract 12 hours and add p.m. (1745 is 5:45 p.m.). 1200 to 1259 is 12:xx p.m., and 0000 to 0059 is 12:xx a.m.

### Is midnight 0000 or 2400?

Both are used. 0000 is midnight at the start of a day and 2400 is midnight at its end, which is the NIST suggestion for avoiding the ambiguous “12 a.m.”. Military time today normally runs from 0000 to 2359.

### How do I add hours to military time?

Add the hours and minutes, carrying 60 minutes to an hour; if the total passes 2400, subtract 24 hours and the result is on the next day. 1745 plus 8 hours 30 minutes is 2615, so 0215 the next day.

### How do I find the hours between two military times?

Subtract the start from the end in hours and minutes. If the end is earlier than the start, the shift runs past midnight: add 24 hours first. 1745 to 0215 is (2400 − 1745) + 0215 = 8 hours 30 minutes, or 8.5 hours.

### How do you say military time?

Say the four digits as hours and minutes: 1430 is “fourteen thirty”, 0900 is “zero nine hundred”, and 1000 is “ten hundred”, never “one thousand”. Some people add “hours” at the end.

## Sources

- NIST, Times of Day FAQs (12 a.m. and 12 p.m. are ambiguous; 24-hour notation can use 0000 for midnight at the start of a day and 2400 for the end of a day). https://www.nist.gov/pml/time-and-frequency-division/times-day-faqs (retrieved 2026-10-02)
- Wikipedia, 24-hour clock, Military time (four digits with no separator, 0000 to 2359; how 12-hour times convert; “hundred”, never “thousand”). https://en.wikipedia.org/wiki/24-hour_clock (retrieved 2026-10-02)