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The Web-Safe Palette

Lynda Weinman, often credited as the inventor of the web-safe palette, has an excellent article on the history and technology of the web-safe palette at lynda.com, and we won't repeat much of it here, except to say that:

• The web-safe palette contains the colors that the early web browsers (Mosaic, Netscape Navigator, and Microsoft Internet Explorer) used themselves for 8-bit colors.
• When you have an 8-bit (256-color) graphics card and the color the browser is supposed to display is one of the colors on the default palette, that's the color they'll display.
• When you have an 8-bit graphics card and the browser is supposed to display a color that isn't on that palette, the browser will dither the color. That means it will tile the space with pixels having colors that it does have in its default pallete that are a little bit lighter and a little bit darker than the color you want. So over an area of pixels — if you stand back far enough — the pixels will average out pretty close to the color you asked for.
• Here's an example. We picked a color that wasn't on the default palette and simulated the way a browser would render it on a PC that had an 8-bit graphics card.

  

  As you can see, it looks pretty bad blown up. Even at normal size, it doesn't look very good.
• As Weinman points out in her article, if you've got big areas of solid color and you expect a lot of visitors to have 8-bit graphics cards, your page will look better if you pick one of the colors on the default palette.
• That palette has been published, and lots of graphics programs will let you specify that palette automatically. But there's one more gotcha: of the 256 available colors in the palette, PCs and Macs render 40 of them differently, leaving 216 colors that are "safe": browsers won't dither them for 8-bit graphics cards, and they look the same on the Mac and the PC. Those 216 colors are called the web-safe palette.
• When your visitors have graphics cards with more than 8-bit color (and most of them do nowadays, even if they don't have a graphics card at all and they're using the built-in graphics chips on their motherboard) the web-safe palette doesn't accomplish anything.
• This is a good thing, since from the standpoint of design, the web-safe colors are mostly pretty awful looking.

Graphics programs often come with the web-safe palette, or you can download it from lynda.com.

Is the web-safe palette dead? Probably.

The Web-Smart Palette

Gamma (what big eyes you have)