In Windows 11, change the system time here:
- Select Start.
- Go to Settings > Time & language > Date & time.
- To set the time automatically, turn Set time automatically On.
- To set the time manually:
- Turn Set time automatically Off.
- Select Change under Set the date and time manually.
- Set the new Date and Time, then select Change.
If the goal is to change how time is displayed, such as 12-hour or 24-hour format:
- Open Control Panel.
- Under Clock and Region, select Change date, time or number formats.
- On the Formats tab:
- For 24-hour format, set Short time to HH:mm and Long time to HH:mm:ss.
- For 12-hour format, set Short time to h:mm:tt and Long time to h:mm:ss:tt.
- Select Apply, then OK.
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