| Home > Internet > HTML > Graphics > 256-colors mode |
Any color which can be specified by any combination of the following six RGB values is supposed to display as non-dithered in IBM-compatible 256-colors video modes.
| hexadecimal | 00 | 33 | 66 | 99 | CC | FF |
|---|---|---|---|---|---|---|
| decimal | 0 | 51 | 102 | 153 | 204 | 255 |
These six values correspond closely to the percentage RGB values 0, 20%, 40%, 60%, 80%, and 100%.
These special supposedly non-dithered colors were referred to in the early days of the Web as "the Netscape magic colors." See my Color names page for a listing of names you can use instead of numeric RGB codes.
| (black) | #000000 | #000033 | #000066 | #000099 | #0000CC | #0000FF | (blue) |
|---|---|---|---|---|---|---|---|
| #003300 | #003333 | #003366 | #003399 | #0033CC | #0033FF | ||
| #006600 | #006633 | #006666 | #006699 | #0066CC | #0066FF | ||
| #009900 | #009933 | #009966 | #009999 | #0099CC | #0099FF | ||
| #00CC00 | #00CC33 | #00CC66 | #00CC99 | #00CCCC | #00CCFF | ||
| (green) | #00FF00 | #00FF33 | #00FF66 | #00FF99 | #00FFCC | #00FFFF | (cyan) |
| #330000 | #330033 | #330066 | #330099 | #3300CC | #3300FF | ||
| #333300 | #333333 | #333366 | #333399 | #3333CC | #3333FF | ||
| #336600 | #336633 | #336666 | #336699 | #3366CC | #3366FF | ||
| #339900 | #339933 | #339966 | #339999 | #3399CC | #3399FF | ||
| #33CC00 | #33CC33 | #33CC66 | #33CC99 | #33CCCC | #33CCFF | ||
| #33FF00 | #33FF33 | #33FF66 | #33FF99 | #33FFCC | #33FFFF | ||
| #660000 | #660033 | #660066 | #660099 | #6600CC | #6600FF | ||
| #663300 | #663333 | #663366 | #663399 | #6633CC | #6633FF | ||
| #666600 | #666633 | #666666 | #666699 | #6666CC | #6666FF | ||
| #669900 | #669933 | #669966 | #669999 | #6699CC | #6699FF | ||
| #66CC00 | #66CC33 | #66CC66 | #66CC99 | #66CCCC | #66CCFF | ||
| #66FF00 | #66FF33 | #66FF66 | #66FF99 | #66FFCC | #66FFFF | ||
| #990000 | #990033 | #990066 | #990099 | #9900CC | #9900FF | ||
| #993300 | #993333 | #993366 | #993399 | #9933CC | #9933FF | ||
| #996600 | #996633 | #996666 | #996699 | #9966CC | #9966FF | ||
| #999900 | #999933 | #999966 | #999999 | #9999CC | #9999FF | ||
| #99CC00 | #99CC33 | #99CC66 | #99CC99 | #99CCCC | #99CCFF | ||
| #99FF00 | #99FF33 | #99FF66 | #99FF99 | #99FFCC | #99FFFF | ||
| #CC0000 | #CC0033 | #CC0066 | #CC0099 | #CC00CC | #CC00FF | ||
| #CC3300 | #CC3333 | #CC3366 | #CC3399 | #CC33CC | #CC33FF | ||
| #CC6600 | #CC6633 | #CC6666 | #CC6699 | #CC66CC | #CC66FF | ||
| #CC9900 | #CC9933 | #CC9966 | #CC9999 | #CC99CC | #CC99FF | ||
| #CCCC00 | #CCCC33 | #CCCC66 | #CCCC99 | #CCCCCC | #CCCCFF | ||
| #CCFF00 | #CCFF33 | #CCFF66 | #CCFF99 | #CCFFCC | #CCFFFF | ||
| (red) | #FF0000 | #FF0033 | #FF0066 | #FF0099 | #FF00CC | #FF00FF | (magenta) |
| #FF3300 | #FF3333 | #FF3366 | #FF3399 | #FF33CC | #FF33FF | ||
| #FF6600 | #FF6633 | #FF6666 | #FF6699 | #FF66CC | #FF66FF | ||
| #FF9900 | #FF9933 | #FF9966 | #FF9999 | #FF99CC | #FF99FF | ||
| #FFCC00 | #FFCC33 | #FFCC66 | #FFCC99 | #FFCCCC | #FFCCFF | ||
| (yellow) | #FFFF00 | #FFFF33 | #FFFF66 | #FFFF99 | #FFFFCC | #FFFFFF | (white) |
Available non-dithered grey shades (also seen above):
| (black) | #000000 | #333333 | #666666 | #999999 | #CCCCCC | #FFFFFF | (white) |
|---|
If you like, you can visualize the large color array as six slices through a 6×6×6 cube, sort of like a Rubik's Cube, with the eight primary colors on the cube's eight corners, and the series of six grey values from black to white forming a diagonal through the center of the cube. Each "slice" has all available Green and Blue combinations for a particular Red value.
256-colors video modes used to be significant to Web authors, because they were sort of the lowest common denominator for Web colors for a while. The old "Standard VGA" 16-colors modes are obsolete, and most systems have high-color or true-color displays now.
Dithering is what a 256-colors video system typically does when it's asked to display a color it doesn't have. It mixes pixels of similar colors it does have, to try to produce an effect that looks more or less right from a distance. Solid colors on Web pages tend to produce more of an impression that the author knew what they were trying to do.
It's not necessarily clear whether more recent browsers in 256-color mode will dither or not in a particular color situation. Netscape tended to dither colors in text and bitmaps, and use the closest match from the "magic colors" in solid background colors.
You can use hexadecimal, decimal, and percentage RGB triplets in CSS style declarations. Hexadecimal triplets can also be used in HTML tags. Paint programs (i.e. Windows Paintbrush, Photoshop, Paint Shop Pro, LView) usually need the decimal RGB values. Color values can be converted between hexadecimal, decimal, and percentages using the Windows Calculator in "Scientific" view mode, or formulas in Excel and OpenOffice.org spreadsheets including the HEX2DEC() and DEC2HEX() functions.
Here are some color attribute code examples.
| Tags | Effect |
|---|---|
| <BODY BGCOLOR="#000000" TEXT="#FFFF00"> </BODY> |
For entire page, set background color to black, and default text color to yellow. (Must be a Star Trek page.) |
| <TABLE BGCOLOR="#00FFFF"> </TABLE> |
Set background color for whole table to cyan; overrides page color. |
| <TR BGCOLOR="#00FFFF"> </TR> |
Set background color for single row of table to cyan; overrides table color. |
| <TH BGCOLOR="#00FFFF"> </TH> <TD BGCOLOR="#00FFFF"> </TD> |
Set background color for single cell of table to cyan; overrides any table and row colors. |
| <P STYLE="color: #FF0000; background: transparent; "> </P> <SPAN STYLE="color: #FF0000; background: transparent; "> </SPAN> |
Set spot text color to red; overrides text color for page.* |
site feedback