The same padding on all four sides

   
      

<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  Title="About WPF" 
  Background="OrangeRed">


    <Canvas>
      <Label Padding="0" Background="Orange">0</Label>
      <Label Padding="10" Background="Orange">10</Label>
    
    </Canvas>

</Window>