How to Convert Military Time: The 24-Hour Clock Made Simple

Quick: is 12:00 AM midnight or noon? Many people pause before they answer, and that pause is where most military time mistakes begin. The 24-hour clock is easy once you know the two rules behind it.

Convert Standard Time to Military Time in Two Steps

Military time is the 24-hour clock written as four digits. It runs from 0000, which is midnight, to 2359, which is the last minute of the day. Minutes never change between the two formats.

Only the hour needs work. For AM times, change hour 12 to 00 and leave every other hour alone. For PM times, keep hour 12 and add 12 to every other hour.

1. Check AM or PM. The period decides which rule you use, so look at it first.
2. Fix the hour. AM keeps the hour, except 12 becomes 00. PM adds 12, except 12 stays 12.
3. Keep the minutes and pad to four digits. Put a zero in front when the hour is a single digit, so 7:30 AM is 0730.

If you want to check a result, our military time converter runs the same steps for you. The strip below shows where each half of the day sits.

Why 12 AM and 12 PM Cause Most Errors

The hour 12 breaks the add-12 habit. 12:00 AM is midnight and becomes 0000, while 12:00 PM is noon and stays 1200. The GPO Style Manual 2016 writes these as 12 a.m. (12 midnight) and 12 p.m. (12 noon).

Here is a quick self-check. Any time from 12:00 AM to 12:59 AM starts with 00. Any time from 12:00 PM to 12:59 PM starts with 12.

Convert Military Time Back to Standard Time

Going backward is just as short. Read the first two digits as the hour and the last two as the minutes. Then use the table to pick AM or PM and fix the hour.

The minutes carry over untouched in every row. So 1745 becomes 5:45 PM, because 17 minus 12 is 5.

Two more checks show the edges. The time 0000 has hour 00, which maps to 12 in the AM, so it is 12:00 AM. The time 1900 has hour 19, and 19 minus 12 is 7, so it is 7:00 PM.

A Worked Example: 2:30 PM to 1430 and Back

Here is one full round trip. We start with 2:30 PM, convert it to military time, and then convert it back to check the work. The flow chart shows the PM decision.

1. Check the period. The time is PM, and the hour is 2, not 12.
2. Add 12 to the hour. Two plus 12 equals 14.
3. Keep the minutes and write four digits. The minutes stay 30, so the result is 1430. It is spoken as “fourteen thirty hours”.
4. Check by going back. Fourteen minus 12 is 2, and the hour is in the PM range, so you get 2:30 PM again.

As a bonus, you can count minutes since midnight. For 1430, that is 14 x 60 + 30, which equals 870 minutes.

Military Time Chart for Every Hour

Sometimes a lookup beats arithmetic. This chart lists every hour on the clock, with the AM hours on the left and the PM hours on the right. Add any minutes to the end of the four-digit number.

Each PM entry sits exactly 12 above the AM entry beside it. That is why the add-12 shortcut works for PM times, and why the 12 o’clock row needs no special treatment in the chart.

How to Write and Say Military Time

Write military time as four digits with no comma. The GPO Style Manual 2016 gives 0025 and 2359 as examples of astronomical and military time. Its rule 12.14 says not to use a comma in these numbers, so write 2359 and not 2,359.

Speaking varies by group. A common spoken form reads 0700 as “oh seven hundred”. That is common usage, not a rule from a cited guide. Our converter reads 1430 as “fourteen thirty hours”.

One style difference is worth knowing. Some style guides use 2400 to mean the end of a day. This article and the calculator use 0000 instead, so the day rolls straight from 2359 to 0000. Follow whichever style your employer, school or agency uses.

Common Mistakes and Where Conversion Stops

Most errors come from using the wrong rule for the period. Watch for these four slips.

• Adding 12 to 12 PM. That gives 2400 instead of 1200.
• Adding 12 to an AM time. It turns 9:00 AM into 2100 when it should be 0900.
• Dropping the leading zero. Writing 730 instead of 0730 breaks the four-digit habit.
• Changing the minutes. They stay the same in both formats.

This guide stops at converting one clock time. It does not cover time zones, daylight saving, seconds, or spans that cross midnight. For math with times, try the time calculator.

Need to turn hours into minutes? The hours to minutes converter handles that. To total work hours for a pay period, the time card calculator is the better fit.

FAQs About Military Time Conversion

Sources and Further Reading

This article is general education. Style rules for writing the 24-hour clock can differ by organization, so follow the guide your employer, school or agency uses. Reviewed for accuracy by Prof. Dr. Khalil Mudassar, PhD. Last updated 2026-10-13.