How can I find a color that complements in another programmatic way?

Question

Given any (user selectable) color, I am trying to create an appropriate color to go with it for the user interface.

Basically, it should be a color that either resembles or complements it very well - but it should also be easily distinguished from the first color. So far I have tried to lighten / darken a color that works fine - but it doesn’t look the best way, I'm not sure there is no better way to do this.

What alternative or better ways can I achieve the desired effect? Any help is much appreciated!

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Side note. I have color in both RGB and HSL formats, although it can be easily converted to others if necessary.

Answer 1

Can you use this site below to help you redesign the concept you are looking for?

http://colorschemedesigner.com/

It blinks, so you cannot see the code, but it can still help.

Answer 2

If you can understand how to create a color wheel, then complementary colors are on opposite sides of the wheel.

Update

Wikipedia has useful pages about hue, hsl and hsv

http://en.wikipedia.org/wiki/Hue

http://en.wikipedia.org/wiki/HSL_and_HSV

and more about conversions

http://130.113.54.154/~monger/hsl-rgb.html