<color>

The <color> data type is specified using one of the options listed below.

Named colors are case-insensitive identifiers that represent a specific color, such as red, blue, black, or lightseagreen. Although the names more or less describe their respective colors, they are essentially artificial, without a strict rationale behind the names used.

The complete list of such keywords is described on the <named-color> page.

The currentcolor keyword represents the value of an element's color property. This lets you use the color value on properties that do not receive it by default.

If currentcolor is used as the value of the color property, it instead takes its value from the inherited value of the color property.

<div style="color: blue; border: 1px dashed currentcolor;">
  The color of this text is blue.
  <div style="background: currentcolor; height:9px;"></div>
  This block is surrounded by a blue border.
</div>

The RGB color model defines a given color in the sRGB color space according to its red, green, and blue components. An optional alpha component represents the color's transparency.

RGB colors can be expressed through both hexadecimal (prefixed with #) and functional (rgb(), rgba()) notations.

Hexadecimal notation: #RGB[A] or#RRGGBB[AA]

R (red), G (green), B (blue), and A (alpha) are hexadecimal characters (0–9, A–F). A is optional. For example, #ff0000 is equivalent to #ff0000ff. The three-digit notation (#RGB) is a shorter version of the six-digit form (#RRGGBB). For example, #f09 is the same color as #ff0099. Likewise, the four-digit RGB notation (#RGBA) is a shorter version of the eight-digit form (#RRGGBBAA). For example, #0f38 is the same color as #00ff3388.

rgb() (and the legacy rgba()): rgb(R G B[ / A]) (or rgb[a](R, G, B[, A])

R (red), G (green), and B (blue) can be either <number>s or <percentage>s, where the number 255 corresponds to 100%. A (alpha) can be a <number> between 0 and 1, or a <percentage>, where the number 1 corresponds to 100% (full opacity).

The HSL color model defines a given color in the sRGB color space according to its hue, saturation, and lightness components. An optional alpha component represents the color's transparency.

hsl(): hsl(H S L [ / A]) (or legacy hsl(H, S, L [, A]))

Where the H is the hue, taking as a value an <angle> of the color circle given in degs, rads, grads, or turns. By definition, red is 0deg, yellow is 60deg, green is 120deg, cyan is 180deg, blue is 240deg, and magenta is 300deg. When written as a unitless <number>, it is interpreted as degrees. The S is the saturation as a <percentage> value where 100% is completely saturated, while 0% is completely unsaturated (gray). The L is the lightness as a <percentage> value where 100% is white, 0% is black, and 50% is "normal". The optional A is alpha transparency as a <percentage> or a <number> between 0 and 1, where the number 1 or 100% and means full opacity and 0 or 0% and means fully transparent.

Many designers find HSL more intuitive than RGB, since it allows hue, saturation, and lightness to each be adjusted independently. HSL can also make it easier to create a set of matching colors (such as when you want multiple shades of a single hue). However, using HSL to create color variations can produce surprising results, as it is not perceptually uniform. For example, both hsl(240 100% 50%) and hsl(60 100% 50%) have the same lightness, even though the former is much darker than the latter.

HSL colors are expressed through the functional hsl() notation.

Similar to HSL color model, the HWB color model defines a given color in the sRGB color space according to its hue, whiteness and blackness components.

As with HSL, HWB can be more intuitive to use than RGB. A hue is specified in the same way, followed by the amount of whiteness and blackness, respectively, in percentage values. This function also accepts an alpha value.

HWB colors are expressed through the functional hwb() notation.

hwb(): hwb(H W B[ / A])

Same as HSL: H (hue) is an <angle> of the color circle given in degs, rads, grads, or turns in the CSS Color specification. When written as a unitless <number>, it is interpreted as degrees, as specified in the CSS Color Level 3 specification. By definition, red=0deg=360deg, with the other colors spread around the circle, so green=120deg, blue=240deg, etc. As an <angle>, it implicitly wraps around such that -120deg=240deg, 480deg=120deg, -1turn=1turn, etc.

W (whiteness) and B (blackness) are percentages. These two colors mix, so you would need 0% whiteness and 100% blackness to produce the color black. And vice versa 100% whiteness and 0% blackness for the color white. 50% of both values renders a mid-grey and any other variations a shade of the hue specified.

A (alpha), optional, can be a <number> between 0 and 1, or a <percentage>, where the number 1 corresponds to 100% (full opacity). When specifying an alpha value it must be preceded with a forward slash (/).

In forced colors mode (detectable with the forced-colors media query), most colors are restricted into a user- and browser-defined palette. These system colors are exposed by the following keywords, which can be used to ensure that the rest of the page integrates well with the restricted palette. These values may also be used in other contexts, but are not widely supported by browsers.

The keywords in the following list are defined by the CSS Color Module Level 4 specification: AccentColor, AccentColorText, ActiveText, ButtonBorder, ButtonFace, ButtonText, Canvas, CanvasText, Field, FieldText, GrayText, Highlight, HighlightText, LinkText, Mark, MarkText, SelectedItem, SelectedItemText, VisitedText.

CSS Color 4 introduced Lab colors. Lab colors are specified via the lab() functional notation. They are not limited to a specific color space, and can represent the entire spectrum of human vision.

CSS Color 4 introduced LCH colors. LCH colors are specified via the lch() functional notation. They are not limited to a specific color space, and can represent the entire spectrum of human vision.

In fact, LCH is the polar form of Lab. It is more human friendly than Lab, as its chroma and hue components specify qualities of the desired color, as opposed to mixing. It is similar to HSL in that way, although it is far more perceptually uniform. Unlike HSL which describes both hsl(60 100% 50%) and hsl(240 100% 50%) as having the same lightness, LCH (and Lab) correctly ascribes different lightness to them: the former (yellow) has an L of 97.6 and the latter (blue) an L of 29.6. Therefore, LCH can be used to create palettes across entirely different colors, with predictable results. Please note that LCH hue is not the same as HSL hue and LCH chroma is not the same as HSL saturation, although they do share some conceptual similarities.

CSS Color 4 introduced this notation. Colors specified via the color() function can specify a color in any of the predefined color spaces, as well as custom color spaces, defined via the @color-profile rule.

In animations and gradients, <color> values are interpolated on each of their red, green, and blue components. By default, animation occurs in an RGBA color space, with interpolation's speed being determined by the timing function in transitions and animations. To prevent unexpected colors from appearing, consider using color-mix() functional notation.

Interpolating the <hue> of two colors in functions that accept a hue angle is also possible and is described in more detail in the color-mix() functional notation documentation.

Some people have difficulty distinguishing colors. The WCAG 2.0 recommendation strongly advises against using color as the only means of conveying a specific message, action, or result. See color and color contrast for more information.

<color> = 
  <absolute-color-base>  |
  currentcolor           |
  <system-color>         

<absolute-color-base> = 
  <hex-color>                |
  <absolute-color-function>  |
  <named-color>              |
  transparent                

<absolute-color-function> = 
  <rgb()>    |
  <rgba()>   |
  <hsl()>    |
  <hsla()>   |
  <hwb()>    |
  <lab()>    |
  <lch()>    |
  <oklab()>  |
  <oklch()>  |
  <color()>  

<rgb()> = 
  rgb( [ <percentage> | none ]{3} [ / [ <alpha-value> | none ] ]? )  |
  rgb( [ <number> | none ]{3} [ / [ <alpha-value> | none ] ]? )  

<hsl()> = 
  hsl( [ <hue> | none ] [ <percentage> | none ] [ <percentage> | none ] [ / [ <alpha-value> | none ] ]? )  

<hwb()> = 
  hwb( [ <hue> | none ] [ <percentage> | none ] [ <percentage> | none ] [ / [ <alpha-value> | none ] ]? )  

<lab()> = 
  lab( [ <percentage> | <number> | none ] [ <percentage> | <number> | none ] [ <percentage> | <number> | none ] [ / [ <alpha-value> | none ] ]? )  

<lch()> = 
  lch( [ <percentage> | <number> | none ] [ <percentage> | <number> | none ] [ <hue> | none ] [ / [ <alpha-value> | none ] ]? )  

<oklab()> = 
  oklab( [ <percentage> | <number> | none ] [ <percentage> | <number> | none ] [ <percentage> | <number> | none ] [ / [ <alpha-value> | none ] ]? )  

<oklch()> = 
  oklch( [ <percentage> | <number> | none ] [ <percentage> | <number> | none ] [ <hue> | none ] [ / [ <alpha-value> | none ] ]? )  

<color()> = 
  color( <colorspace-params> [ / [ <alpha-value> | none ] ]? )  

<alpha-value> = 
  <number>      |
  <percentage>  

<hue> = 
  <number>  |
  <angle>   

<colorspace-params> = 
  <predefined-rgb-params>  |
  <xyz-params>             

<predefined-rgb-params> = 
  <predefined-rgb> [ <number> | <percentage> | none ]{3}  

<xyz-params> = 
  <xyz-space> [ <number> | <percentage> | none ]{3}  

<predefined-rgb> = 
  srgb          |
  srgb-linear   |
  display-p3    |
  a98-rgb       |
  prophoto-rgb  |
  rec2020       

<xyz-space> = 
  xyz      |
  xyz-d50  |
  xyz-d65  

In this example we provide a <div> and a text input. Entering a valid color into the input causes the <div> to adopt that color, allowing you to test our color values.

HTML

<div></div>
<hr />
<label for="color">Enter a valid color value:</label>
<input type="text" id="color" />

CSS

div {
  width: 100%;
  height: 200px;
}

const inputElem = document.querySelector("input");
const divElem = document.querySelector("div");

function validTextColor(stringToTest) {
  if (stringToTest === "") {
    return false;
  }
  if (stringToTest === "inherit") {
    return false;
  }
  if (stringToTest === "transparent") {
    return false;
  }

  const image = document.createElement("img");
  image.style.color = "rgb(0, 0, 0)";
  image.style.color = stringToTest;
  if (image.style.color !== "rgb(0, 0, 0)") {
    return true;
  }
  image.style.color = "rgb(255, 255, 255)";
  image.style.color = stringToTest;
  return image.style.color !== "rgb(255, 255, 255)";
}

inputElem.addEventListener("change", () => {
  if (validTextColor(inputElem.value)) {
    divElem.style.backgroundColor = inputElem.value;
    divElem.textContent = "";
  } else {
    divElem.style.backgroundColor = "white";
    divElem.textContent = "Invalid color value";
  }
});

Result

This example shows the many ways in which a single color can be created with the various RGB color syntaxes.

/* These syntax variations all specify the same color: a fully opaque hot pink. */

/* Hexadecimal syntax */
#f09
#F09
#ff0099
#FF0099

/* Functional syntax */
rgb(255,0,153)
rgb(255, 0, 153)
rgb(255, 0, 153.0)
rgb(100%,0%,60%)
rgb(100%, 0%, 60%)
rgb(100%, 0, 60%) /* ERROR! Don't mix numbers and percentages. */
rgb(255 0 153)

/* Hexadecimal syntax with alpha value */
#f09f
#F09F
#ff0099ff
#FF0099FF

/* Functional syntax with alpha value */
rgb(255, 0, 153, 1)
rgb(255, 0, 153, .5)
rgb(255, 0, 153, 0.5)
rgb(255, 0, 153, 100%)

/* Whitespace syntax */
rgb(255 0 153 / 1)
rgb(255 0 153 / 100%)

/* Functional syntax with floats value */
rgb(255, 0, 153.6, 1)
rgb(2.55e2, 0e0, 1.53e2, 1e2%)

• The opacity property lets you define transparency at the element level.
• The <hue> data type represents a color by hue angle.
• Some common properties that use this data type: color, background-color, border-color, box-shadow, outline-color, text-shadow
• Applying color to HTML elements using CSS
• New functions, gradients, and hues in CSS colors (Level 4) on MDN blog (May 3, 2023)