Pantone
"In 1963, Lawrence Herbert, Pantone’s founder, created an innovative system for identifying, matching and communicating colors to solve the problems associated with producing accurate color matches in the graphic arts community. His insight that the spectrum is seen and interpreted differently by each individual led to the innovation of the PANTONE MATCHING SYSTEM®, a book of standardized color in fan format. Pantone has since expanded its color matching system concept to other color-critical industries, including digital technology, fashion, home, plastics, architecture and contract interiors, and paint. Today, the PANTONE® Name is known worldwide as the standard language for accurate color communication, from designer to manufacturer to retailer to customer, across a variety of industries."

Behr Paint and Wood Stain
This interior decoration site offers an "Explore Color" tab that helps you find coordinating colors. Although these colors are limited to Behr selections, using the ColorSmart interactive selection tool produces eight combinations based on a "main color" and may be useful for generating ideas for your own designs.

Color Matters J.L. Morton's site explores the science, psychology, sociology, and use of color.

CMYK Color Space Discussion. Color space fundamentals.

Hexadecimal Color Information

Color Blender
Put two valid CSS color values, in the format you choose--hex, RGB, RGB%--then choose the number of midpoints you'd like between them and blend. You'll get intermediate colors with their hexadecimal codes.

Color Scheme
Find color analogic, contrasting, and monochromatic schemes and test them with various vision abnormalities. Also see Color Scheme Generator 2 where you can limit to "safe" web colors and enter an RGB code for a rough conversion.

Color Schemer
Lets you lighten or darken a color scheme and displays hexadecimal codes.

Color Match 5K
"This utility will help you select a matching 6-color palette for your website. Define a single color that you like. Matching colors will be calculated." Includes the hexadecimal codes under each color.

Color Wheel Color Calculator
Provided by the Sessions School of Design, "the Sessions Color Calculator is an interactive color wheel that helps designers select HTML, RGB, or CMYK colors and identifies color harmonies and schemes. Designers may save HTML safe color values, CMYK color schemes, or RGB colors to an integrated clipboard and email the colors to colleagues or clients. You can also rotate shapes on the color wheel to identify harmonious color schemes, adjust the saturation and lightness of colors, or select a color plan to use for a corporate identity or design project."

Hex Color Codes and How to Use Them.
Includes browser safe color chart and explanations.

HTML Color Codes
Dynamic color chart and color picker. With color picker you can get HTML color codes for all 16.7 million RGB colors.

HTML Color Codes: a VisiBone Wheel.
Bob Stein has arranged the 216 hexadecimal HTML color codes by hue and presents them as cards, charts and swatches, some free and some at cost.

Infohound Colour Schemer
"This color schemer is a simple tool to help you experiment with various color schemes for your next web or print project. Click around within the shaded box to set the saturation and brightness, or within the rainbow to set the hue. You can also enter a particular value directly into one of the boxes."

Lissa Explains It All: RGB Hex Decimal Conversion
Interesting feature of this site is a "color slider" in section 2 that finds the code for a color you want.

moreCrayons
"moreCrayons is primarily a resource for web designers and developers to test [an] expanded palette of 4,096 colors for the web. The web-smart palette pages show different demonstrations of the palette. The Resources section has links to articles about color and tools for using color on the web."

Online PMS Color Chart and PMS Color Chart
"Use this guide to assist your color selection and specification process. Do not rely on it as your only method for final color selection. This chart is a reference guide only. Pantone colors on computer screens may vary based on the graphics card and monitor used in your system. For true accuracy use the Pantone Color Publication."

Palette Man
Select up to 4 colors and see how they interact with one another. You can also select preset color combinations such as "romantic," "industrial," etc.

Tech Color Graphics. Inc.
Technical help links on bleeds, CMYK color, duotones, dot gain, preflight, resolution, etc.

Web Safe Colours
This section of the cloford.com website provides a web-safe diagram, web-smart colours, named colours, 500+ colours, web-safe colours by hue, and colour links.