Simple tool to visualize urn problems. The options should be self explainatory, just try them out. Colors can be CSS colors (scroll down to the table for available color names) or given as RGB value in the form #rgb where r is for the red value between 0 and f (hexadecimal 0,1,...,9,a,b,...,f), g for green and b for blue.
To save the image, use right click -> Save Image As or similar.