Windows 10 can display time in either a 12-hour format with AM/PM or a 24-hour format such as 18:30. The setting comes from Windows’ regional time format rather than the clock application itself.
Switch Windows to 24-hour time
- Open Settings.
- Select Time & Language and open the regional formatting options available on your Windows 10 version.
- Choose Change data formats or the equivalent regional-format settings.
- Set Short time to a format that begins with HH, such as HH:mm.
- Set Long time to a 24-hour format as well if you want seconds or long-time displays to match.
- Check the taskbar clock and an application that uses Windows regional settings.
What the format symbols mean
In Windows formatting, a capital H represents the 24-hour clock, while a lowercase h represents the 12-hour clock. A format that includes tt normally displays the AM or PM designator. You usually do not need to change the time zone or the actual system time to change how the clock is displayed.
Some apps have their own time setting
Programs and websites can ignore the Windows regional format and use an application, account, or server preference instead. If the taskbar shows 24-hour time but one program does not, check that program’s settings before changing Windows again.
Windows 10’s regular support ended in October 2025. The formatting control remains useful on existing installations, but PCs that support Windows 11 should move to a supported Windows version for long-term security.
Kermit Matthews is a freelance writer based in Philadelphia, Pennsylvania with more than a decade of experience writing technology guides. He has a Bachelor’s and Master’s degree in Computer Science and has spent much of his professional career in IT management.
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