Getting colors to behave and work together on a web page is a challenging task. Luckily, there are plenty of helpful tools available for free on the web.

Here’s a rundown of my favorites:

If you never took art class in high school, start by checking out this brief introduction to color theory. It goes through all the basics like: Primary, Secondary and Tertiary Colors, Tints, Shades, and Tones, Complementary, Analogous, Triadic schemes.

One of the slickest tools out there is kuler made by Adobe. Boasting an easy-to-use flash interface, it lets you refine a color scheme based on a color, image or choose a scheme shared by one of the community members. If you sign in with your free Adobe ID, you can save your work, download files and more.

For quick and easy testing, I like to use Color Scheme Generator 2. Provide a base color, then let the app suggest pleasing schemes based on color theory – things like monochromatic schemes, analogic colors, or “soft” contrast.

Quite a few sites allow designers to share color schemes. My favorites are Colour Lovers, Colorcombos.com and the Color Schemer Gallery. You can search for a color scheme by title or by base color (like, find every color scheme containing #80C31C).

Colorcombos.com also has a neat feature that displays your colors in big blocks on the screen, so you can see how they look together.

Nature is a consistent source of good color combos. Use the color palette generator to “color-palette-ify” your favorite image. Simply enter the URL of your inspiration and color palette generator will give you the 5 most common colors in the photo.

Similarly, colr.org picks out the color scheme from your favorite photo, a random Flickr photo or a website. It’s minimalist interface packs some interesting features like tagging your colors and browsing iStockPhotos that match your color scheme.