Click on the "Try it Yourself" button to see how it works.
The window to the left is editable - edit the code and click on the "Run" button to view the result in the right window.
The "Result Size" returns the width and the height of the result window in pixels (even when you resize the browser window).
You can control the size of a window with the bar in between the windows (draggable gutter).
The icons are explained in the table below:
|Go to www.w3schools.com|
|Menu button for more options|
|Save your code (and share it with others)|
|Change orientation (horizontally or vertically)|
|Change color theme (dark or light)|