This is a very handy tool for choosing tones of the same color or midtones of two colors. If you like your website to be abstract in color opposing colors are fine but if you want something that draws the eye in tonal colors are more pleasing to the eye in my humble opinion.
I was searching the internet for something free to download when I came across this site. I just love it for picking tonal colors. The site is here and this is what you come to:
The red dot is format and if you are working in psp or php, especially making web pages or working with CSS you will want to use the Hex option which will give you a # and six numbers or letters, also referred to as html colors. The black dot where the box is yellow is highlighted to let you know what box you are working in. Highlight the top box first and choose the color you want there from the color chart on the right or a color number you already have in mind. You can click on the little boxes of the color chart to choose a color after you have your top box highlighted. The blue dot is the first color you choose or start out with and it goes in the top box.
The green dot is the second color you choose. If you want to stay in the same tonal range go to the top of the color chart and choose white like the example, after you highlight the second box. It doesn't have a black outline if you choose white. I put it there so you could see where it is in this tutorial. The yellow dot is the midpoint range of colors between the two you choose. There is an arrow by the number and if you click that you can get between 1 and 10 color choices in between the two you choose. I chose the most so you could see the wide range of colors.
The gray dot is the button you click on to activate the color blend mode. It will bring up all the colors in between the two. The pink dot clears your palette so you can start over.
Below I have chosen two very different blues. If for any reason you are working with several different colors of the same shade but with different tonal values and the colors are going to be either close together or on top of each other and you need some harmony put the two colors in the top and bottom boxes color 1 and 2, choose aa many midpoints of color you think you might use and go with one of the colors in the middle like the third or fourth color in this example.
This tut is copyrighted to the tut owner(me-Red), it would be nice if you want to use it to ask permission, just a thought.