In HTML, colors are expressed as either hexadecimal values (for example, "#FF0000") or as color names ("red"). The 216 colors that are common to Netscape and Internet Explorer on both Windows and the Macintosh are called browser safe. Any hexadecimal value that combines the pairs 00, 33, 66, 99, CC, or FF (RGB values 0, 51, 102, 153, 204, and 255, respectively) is browser safe.

All of the color pickers in Dreamweaver have browser-safe palettes. Selecting a color from a palette displays the color's hexadecimal value. To edit this value, type in the text box next to the color swatch; or to choose a color outside the browser-safe range, click the palette icon in the lower right corner of the color picker, and select a color.

UNIX versions of Netscape use a different color palette than the Windows and Macintosh versions. If you are developing exclusively for UNIX machines (or your target audience is Windows or Macintosh users with 24-bit monitors and UNIX users with 8-bit monitors), consider using hexadecimal values that combine the pairs 00, 40, 80, BF or FF, which produce browser-safe colors on the SunOS.