Show Seconds in Windows 10 Clock contains the batch files to show or hide seconds in the Windows 10 taskbar clock, then restart explorer.exe, so the changes are seen without rebooting or logging out.
If you'd prefer not to use batch files, you can make the registry changes yourself by following our tutorial here. The only reason for using a batch file, rather than registry files, is to restart Explorer, saving you from rebooting to see the changes.
Download Show Seconds in Windows 10 Clock and extract the two files.
Double-click on Hide Seconds Taskbar Clock.bat or Hide Seconds Taskbar Clock.bat.
The changes will be applied and your screen will flash as explorer restarts.
You can now see the seconds in your Windows 10 taskbar clock.