Military time uses a 24-hour format instead of AM and PM

Military time, also called 24-hour time, runs from 00:00 (midnight) to 23:59 (one minute before the next midnight). Instead of splitting the day into AM and PM, it numbers every hour from 0 to 23. The first 12 hours of the day stay the same — 1:00 AM is 01:00 in military time — but the afternoon and evening shift: 1:00 PM becomes 13:00, 6:00 PM becomes 18:00, and 11:00 PM becomes 23:00.

Most digital devices let you switch to this format in the settings. The exact steps depend on what you are using: a phone, computer, smartwatch, or a physical clock with a display. Once you change the setting, your device will show all times in 24-hour format until you switch it back.

Key Takeaways

  • Military time numbers hours from 00 to 23 instead of using AM and PM, so 1:00 PM displays as 13:00.
  • On iPhones, go to Settings > General > Date & Time and turn on 24-Hour Time.
  • On Android phones, open Settings > System > Date & Time and toggle the 24-hour format switch.
  • Windows computers use Settings > Time & Language > Date & Time, then toggle the 24-hour clock option.
  • Mac computers require System Settings > General > Date & Time, then choosing a 24-hour format from the Time format dropdown.

How to change an iPhone to military time

Open the Settings app on your iPhone. Scroll down and tap General, then tap Date & Time. Look for the toggle labeled 24-Hour Time and turn it on. The switch will turn green when it is active.

Once you enable this setting, your iPhone will display the time in 24-hour format everywhere: on the lock screen, in the status bar at the top, in the Clock app, and in all other apps that show the time. The change takes effect when ready. You can turn it off the same way by returning to Settings > General > Date & Time and toggling 24-Hour Time back off.

How to change an Android phone to military time

Open the Settings app. Tap System (or Device if your phone uses a different menu structure), then tap Date & Time. Look for the option labeled Use 24-hour format or 24-hour time and toggle it on. The switch will show as enabled when it is active.

Some Android phones place this setting under Settings > Apps > Clock instead, depending on the manufacturer and Android version. If you cannot find it under System, try opening your Clock app directly and looking for a settings or preferences menu within that app. The change applies to your entire phone once enabled.

How to change a Windows computer to military time

Click the Start button and open Settings. Go to Time & Language, then select Date & Time from the left menu. Scroll down to the Related settings section and click Additional date, time, & regional settings.

In the window that opens, click Change date and time format. Under the Formats tab, find the Time format dropdown menu. Select a 24-hour format from the list — it will show times like 13:00:00 instead of 1:00:00 PM. Click OK to save the change. Your system clock and all timestamps will now display in 24-hour format.

How to change a Mac to military time

Click the Apple menu in the top-left corner and select System Settings. Click General in the sidebar, then click Date & Time. Under the Time format section, you will see a dropdown menu currently set to 12-hour or 24-hour. Click the dropdown and select 24-hour format.

The change takes effect when ready. Your Mac will display the time in 24-hour format on the menu bar, in the Dock, and throughout the system. To switch back to 12-hour time, return to System Settings > General > Date & Time and select 12-hour from the same dropdown.

How to change a smartwatch to military time

The steps vary by smartwatch brand. On an Apple Watch, open the Watch app on your paired iPhone, go to General > Date & Time, and toggle on 24-Hour Time. The watch will sync this setting automatically.

On a Wear OS smartwatch (used by Samsung, Google, and others), open Settings on the watch itself, go to System > Date & Time, and toggle on 24-hour format. Some fitness watches like Garmin have their own companion apps: open the app on your phone, find the clock or time settings, and look for a 24-hour option there. Check your watch's manual or the manufacturer's support page if you cannot locate the setting.

Converting between 12-hour and 24-hour time

To convert from 12-hour to 24-hour time, add 12 to any PM hour except 12:00 PM itself. So 3:00 PM becomes 15:00 (3 + 12), and 9:30 PM becomes 21:30 (9 + 12). Midnight is 00:00, and noon is 12:00.

To convert from 24-hour back to 12-hour time, subtract 12 from any hour 13 or higher. So 18:00 becomes 6:00 PM (18 − 12), and 22:45 becomes 10:45 PM (22 − 12). Hours 00:00 through 00:59 are the AM hours just after midnight, and 01:00 through 11:59 are the rest of the morning and early afternoon.

Frequently Asked Questions

Will changing to military time affect my alarms or scheduled events?

No. Your alarms and calendar events will continue to work normally. The change only affects how the time is displayed on your screen. If you set an alarm for 6:00 PM before switching to 24-hour time, it will still go off at the same moment — the device will just show it as 18:00 instead.

Can I use military time on only some apps?

No. The 24-hour format setting is system-wide on phones and computers. Once you enable it in your device settings, all apps will display time in 24-hour format. Some individual apps may have their own time format options, but most will follow your device's main setting.

What is the difference between military time and UTC?

Military time is straightforward 24-hour format — it is how you display the time. UTC (Coordinated Universal Time) is a time zone, like Eastern or Pacific time. You can display UTC in 12-hour or 24-hour format. Military personnel and many organizations use 24-hour format, but that does not mean they are using UTC; they may be using their local time zone in 24-hour format.

Do I need to restart my device after changing to military time?

No. The change takes effect when ready on all modern phones and computers. You will see the new 24-hour format on your screen right away without restarting.

How do I know what time 14:30 is in regular time?

Subtract 12 from any hour 13 or higher. So 14:30 minus 12 equals 2:30 PM. For times between 00:00 and 00:59, those are AM hours just after midnight. For times between 01:00 and 11:59, add AM to read them as you normally would.