X11 color names

The first versions of Mosaic and Netscape Navigator used the X11 colors as the basis for the web colors list, as both were originally X applications. The W3C specifications SVG and CSS level 3 module Color eventually adopted the X11 list with some changes. The present W3C list is a superset of the 16 "VGA colors" defined in HTML 3.2 and CSS level 1. One notable difference between X11 and W3C is the case of "Gray" and its variants. In HTML, "Gray" is specifically reserved for the 128 triplet (50% gray) . However, in X11, "gray" was assigned to the 190 triplet (74.5%) , which is close to W3C "Silver" at 192 (75.3%) , and had "Light Gray" at 211 (83%) and "Dark Gray" at 169 (66%) counterparts. As a result, the combined CSS 3.0 color list that prevails on the web today produces "Dark Gray" as a significantly lighter tone than plain "Gray" , because "Dark Gray" was descended from X11 – for it did not exist in HTML nor CSS level 1 – while "Gray" was descended from HTML. Even in the current draft for CSS 4.0, dark gray continues to be a lighter shade than gray. Some browsers such as Netscape Navigator insisted on an "a" in any "Gray" except for "Light Grey". Recent X releases (since 2014, xorg-rgb version 1.0.6) also support the W3C definitions. In X11, the original definitions have been preserved (so "Dark Gray" remains a darker shade of "Gray"), but for every conflicting name pair, "Web" and additional "X11" prefixes have been added to ease disambiguation after the merger. The "X11" prefix is an alias for the non-prefixed version, i.e. "X11 Gray" = "Gray" ≠ "Web Gray". The W3C also defined a color that is equal to X11's "Green", but called it "Lime". In X11, this is simply called "Lime", as no such name existed before. It aliases to "Green", i.e. "Lime" = "Green" = "X11 Green" ≠ "Web Green". == Color name chart ==

The following chart presents the standardized X11 color names from the X.org source code. The list of names accepted by browsers following W3C standards slightly differs as explained above. The table does not show numbered gray and brightness variants as described below. Actual rgb.txt files and other color databases or palettes may differ since they are freely editable by vendors and users. The table shows component values in several notations of the RGB color space, with conversions to HSL and HSV assuming sRGB color space. == Color variations ==

Shades of gray The complete rgb.txt defines 101 shades from 'Gray0' (black) up to 'Gray100' (white) in addition to 'Gray' and its variants listed above. The shades are apparently defined by the formula GrayN := round(N% × 255) resulting in e.g. 'Gray96' , which happens to be the same as 'White Smoke'. Similarly 'Dim Gray' is the same as 'Gray41' . On the other hand, 'Gray' lies between 'Gray74' and 'Gray75' ; 'Dark Gray' is not the same as 'Gray66' ; and 'Light Gray' is not the same as 'Gray83' . These shades are not included in W3C specifications, although drafts for level 4 of the CSS Color module include a similar function gray(). They are still coded without 'Grey' alternatives, but with no space before the digit. Numbered variants For 78 colors (not counting grays), rgb.txt offers four variants "color1", "color2", "color3", and "color4", with "color1" sometimes corresponding to "color", so e.g. "Snow1" is the same as "Snow". Unlike base colors, e.g. cadet blue and CadetBlue, these are only coded without spaces, e.g. CadetBlue3. These variations are neither supported by popular browsers nor adopted by W3C standards. Whether or not a certain color has such variants seems random. If "color1" is not the same as "color, the base color is usually darker. That means its brightness in HSB color notation is less than 100%; about 30 of the base colors are fully bright. The four variants (1...4) have rounded brightness values of 100%, 93%, 80% and 55%, respectively. Their hue and saturation are usually the same except for rounding. In some cases they differ from the base color, though, which may indicate that these variants were specified with alternate definitions of the bases in mind, i.e. their values were adapted to a certain monitor which was commonly done by vendors until the 1990s. The fixed brightness settings correspond closely to these formulae to determine the RGB values: color1 := color × 100% color2 := color1 × 93.2% color3 := color1 × 80.4% color4 := color1 × 54.8% Examples: • "Yellow 2" (238, 238, 0) is based on "Yellow" (255, 255, 0) with 255 × 0.932 = 237.66. • "Ivory 3" (205, 205, 193) is explained by "Ivory" (255, 255, 240) where 255 × 0.804 = 205.02 and 240 × 0.804 = 192.96. • "Azure 4" (131, 139, 139) is close to "Azure" (240, 255, 255) values transformed as 255 × 0.548 = 139.74 and 240 × 0.548 = 131.52. Prefixed variants Some color names appear to be brightness or saturation modifications of others because they bear prefixes such as Dark, Light, Medium, Pale or Deep, but there is no systematic variation apparent. Several sets, however, feature a Dark variant with 55% brightness and some have their Medium at about 80%. "Light Goldenrod Yellow" and "Dark Olive Green" are special, because there are no corresponding color entries without Dark and Light prefixes. Nuances with different hue Several groups of colors share the same lightness or brightness and saturation. These nuances differ only by hue. ; 100%/25%: 0° (Web) Maroon, 60° Olive, 120° Green, 180° Teal, 240° Navy (Blue), 300° (Web) Purple ; 100%/27%: 0° Dark Red, 180° Dark Cyan, 240° Dark Blue, 300° Dark Magenta ; 100%/41%: 181° Dark Turquoise, 282° Dark Violet ; 100%/49%: 90° Lawn Green, 157° Medium Spring Green ; 61%/50%: 80° Yellow Green, 120° Lime Green, 280° Dark Orchid ; 100%/50%: 0° Red, 16° Orange Red, 33° Dark Orange, 39° Orange, 51° Gold, 60° Yellow, 90° Chartreuse, 120° (Lime) Green, 150° Spring Green, 180° Aqua / Cyan, 195° Deep Sky Blue, 240° Blue, 300° Fuchsia / Magenta ; 25%/65%: 0° Rosy Brown, 120° Dark Sea Green ; 59–60%/65%: 260° Medium Purple, 302° Orchid, 340° Pale Violet Red ; 100%/86%: 38° Moccasin, 351° Light Pink ; 100%/90%: 36° Blanched Almond, 54° Lemon Chiffon ; 67%/94%: 30° Linen, 240° Lavender ; 100%/94%: 6° Misty Rose, 60° Light Yellow, 180° Light Cyan ; 100%/97%: 25° Seashell, 40° Floral White, 60° Ivory, 120° Honeydew, 180° Azure, 208° Alice Blue, 340° Lavender Blush ; 100%/99%: 0° Snow, 240° Ghost White Tints and shades with different lightness Several groups of colors share the same hue and HSL saturation. Tints are lighter than a base color, shades are darker. ; 0°/0%: 0% Black, 41% Dim Gray, 50% (Web) Gray, 66% Dark Gray, 75% (X11) Gray, 75% Silver, 83% Light Gray, 86% Gainsboro, 96% White Smoke, 100% White ; 0°/100%: 25% (Web) Maroon, 27% Dark Red, 50% Red, 99% Snow ; 16°/100%: 50% Orange Red, 66% Coral ; 33°/100%: 50% Dark Orange, 88% Bisque ; 36°/100%: 84% Navajo White, 90% Blanched Almond ; 60°/100%: 25% Olive, 50% Yellow, 94% Light Yellow, 97% Ivory ; 80°/61%: 35% Olive Drab, 50% Yellow Green ; 90°/100%: 49% Lawn Green, 50% Chartreuse ; 120°/61%: 34% Forest Green, 50% Lime Green ; 120°/100%: 20% Dark Green, 25% (Web) Green, 50% (X11) Green / Lime, 97% Honeydew ; 146–147°/50%: 36% Sea Green, 47% Medium Sea Green ; 150°/100%: 50% Spring Green, 98% Mint Cream ; 180–181°/100%: 25% Teal, 27% Dark Cyan, 41% Dark Turquoise, 50% Aqua / Cyan, 94% Light Cyan, 97% Azure ; 240°/100%: 25% Navy Blue, 27% Dark Blue, 40% Medium Blue, 50% Blue, 99% Ghost White ; 300°/100%: 25% (Web) Purple, 27% Dark Magenta, 50% Fuchsia / Magenta ; 328–330°/100%: 54% Deep Pink, 71% Hot Pink ; 350–351°/100%: 88% Pink, 86% Light Pink Tones with different saturation Some pairs of colors share the same lightness and hue. These tones differ only by saturation. Tones are far less common in the X11 set than nuances, tints and shades. ; 0°/41%: 0% Dim Gray, 59% Brown ; 120°/50%: 61% Lime Green, 100% Green / Lime ; 180°/25%: 25% Dark Slate Gray, 100% Teal ; 240°/27%: 64% Midnight Blue, 100% Dark Blue == Derived lists ==

The Printer Working Group (PWG) of the IEEE publishes a standard, PWG 5101.1, whose mandatory color names are based upon RFC 3805, successor to RFC 1759 which imported the functional color names other, unknown and transparent alongside seven basic colors from ISO 10175 (DPA) and ISO 10180 (SPDL), and JTAPI. This standard has four variants for each non-monochromatic color: clear (50% transparent), dark, light and the default. Wherever possible, the values are the same as in the W3C adaptation of the X11 list, except for Turquoise which is instead of . Missing variant values have been added systematically. Buff and Mustard are completely new color names. Light Black and Gray correspond to the same color. == See also ==