how to make taskbar icons smaller in windows 10

 

You can modify the size of your taskbar icons through the Taskbar settings.
  1. Right-click the taskbar.
  2. Select Taskbar settings.
  3. Set Use small taskbar buttons to On.
How do I reduce the size of my taskbar icons?
Change the size of Taskbar icons

Right-click on any empty space on your desktop and click View from the drop-down menu. 2. Select either Large icons, Medium icons, or Smaller icons. You’ll see an automatic change in the size of your Taskbar icons.