1030 Military Time

1030 is half past ten in the morning, 10:30 AM. The first two digits are the hour, the last two are the minutes, and the minutes are the same in every system: 30 stays 30. Only the hour needs attention: the hour is below 12, so add AM: 10 o’clock in the morning.

Ten in the morning, the first hour written without a leading zero. From here the pattern is simply the number plus “hundred”: ten hundred, eleven hundred, twelve hundred.

1030 sits 10.5 hours after midnight. A standard eight-hour shift that starts at 1030 ends at 1830; a twelve-hour shift ends at 2230.

Every single minute of this hour is listed on the 1000 page.

Adding whole hours to military time is a plain sum until you pass 2359, then you subtract 24 and move to the next day. A shift from 1030 that lasts eight hours ends at 1830. For a shift with a break, the work hours calculator does the subtraction and accepts both formats.

Military to 12-hour. The hour is below 12, so add AM: 10 o’clock in the morning. Keep the 30 minutes: 1030 is 10:30 AM.

12-hour to military. 10 AM keeps its number; it already has two digits, so nothing is added: 10:05 AM is 1005. So 10:30 AM is 1030: no colon, no AM, four digits.

The common slip is writing “10:30 AM”, which mixes the two systems. The evening counterpart of 1030 is 2230, twelve hours later.

1030 is said “ten thirty”. With minutes attached, the word “hundred” disappears; “ten hundred thirty” is wrong, and so is “ten thirty hundred”. It is the same words you would use for the number 10 followed by the number thirty.

Minutes follow the same logic. 1005 is “ten zero five” and 1040 is “ten forty”. Single-digit minutes get a spoken zero, so the listener knows a digit is there.

About the word “hours”: in speech, “ten hundred hours” is everywhere, and nobody will correct you. In writing, Army Regulation 25-50 says the word is not used with military time, so a memorandum reads “at 1030”, not “at 1030 hours”.

On its own, 1030 is local time wherever it is written. When the four digits carry a letter, the letter is the time zone. Z stands for Zulu, which is UTC, and J (Juliet) means the local time of the person speaking. The table converts 1030Z to the four US zones, in standard time and in daylight saving time.

Eastern Time is four hours behind UTC from March to November and five hours behind the rest of the year, which is why one Zulu time maps to two possible local times. The other three zones follow the same pattern an hour further west each.

Midnight has a second spelling, 2400, used when it marks the end of a day rather than the start. The full rules, with a converter, are on the military time chart page.