Online Combination Calculator Is There Such A Thing As A Paint Color 'calculator'?

Is there such a thing as a paint color 'calculator'? - online combination calculator

What I want is something on the Internet where you can select a main color and give you some ideas to find the center of gravity. For example, choose a light gray color and is 4 or 5 different combinations, which would work. If someone could make a link I would be delighted!