TypeScript rewrite of chroma-js. Includes:
- Proper ES module support.
- Included typings generated from the source.
- A number of bugfixes.
- No more
NaNvalues. - Exceptions on invalid inputs.
- Better inline documentation.
- Smaller (11.26 KB gzipped).
npm install --save chroma.ts
// in TypeScript / using ES modules
import * as chroma from 'chroma.ts'
// commonjs
const chroma = require('chroma.ts')
chroma.css('powderblue') // create a color
.darker(2) // transform it
.gl() // output itAlternatively, you can include the UMD bundle in a script tag and use the chroma global.
example chroma.color(99, 99, 44, 0.7) 
.color(x: Chromable, format?: ColorFormat): Color src
example chroma.color('mediumorchid') // a css string 
example chroma.color([56, 203, 30]) // a RGB triple 
example chroma.color(0x4b0082) // a hex num 
example chroma.color([30, 0.8, 0.3], 'hsl') // explicit format 
This overload allows VS Code to suggest color names when you type color('.
.color(channel0: number, channel1: number, channel2: number, format: ColorFormat): Color src
example chroma.color(30, 0.8, 0.3, 'hsl')
.color(channel0: number, channel1: number, channel2: number, channel3: number, format: ColorFormat): Color src
example chroma.color(0.3, 0.8, 0.3, 1, 'gl') 
type Chromable = number | string | Color | number[]
A Chromable is any value which can be converted to a color. For ease of use, most functions accept these instead of only Color values.
color.mix(col2: Chromable, f: number, m: InterpolationMode = "rgb"): Color src
@see [[mix]]
color.hex(mode: "rgb" | "rgba" | "argb" = "rgb"): string src
Return a hex-string representation of this color.
@see #num for a hex-number representation.
example chroma.color('yellow').alpha(0.7).hex() "#ffff00"
example chroma.color('yellow').alpha(0.7).hex('rgba') "#ffff00b3"
example chroma.color('yellow').alpha(0.7).hex('argb') "#b3ffff00"
Returns the [HSL] representation of this color. hue will always be in [0;360). Values are never NaN.
example chroma.color('purple').hsl() [300, 1, ~0.25]
Returns the [HSL] representation of this color. hue will always be in [0;360). Values are never NaN.
example chroma.color('purple').hsv() [300, 1, ~0.5]
Returns the [HSL] representation of this color. hue will always be in [0;360). Values are never NaN.
example chroma.color('purple').hcg() [300, ~0.5, 0]
color.css(mode: "rgb" | "hsl" = "rgb"): string src
Returns a CSS rgb(...) or hsl(...) string representation that can be used as CSS-color definition. The alpha value is not output if it 1.
example chroma.color('teal').css() "rgb(0,128,128)"
example chroma.color('teal').alpha(0.5).css() "rgba(0,128,128,0.5)"
example chroma.color('teal').css('hsl') "hsl(180,100%,25.1%)"
color.name(closest: true): string src
color.name(closest: false | true = false): string | undefined src
Get the name of a color. By default, this method will try to match the color exactly (comparing rounded RGB values). Pass true to return the name of the color which is closest to this in CIELAB color space. CIELAB is used as it is perceptually uniform.
example chroma.color('#ff0000').name() "red"
example chroma.color('#ff0001').name()
example chroma.color('#ff0001').name(true) "red"
Get the CMYK representation of this color.
example chroma.color('red').cmyk() [0, 1, 1, 0]
Returns the [GL] representation of this color.
example chroma.color('33cc00').gl() [0.2, 0.8, 0, 1]
color.luminance(): number src
Get luminance of the color. This is equal to the Y channel of the XYZ color space.
example chroma.color('black').luminance() 0
example chroma.color('white').luminance() ~1
example chroma.color('red').luminance() ~0.21
@see https://en.wikipedia.org/wiki/Relative\_luminance
color.luminance(lum1: number): this src
Return a new [Color] with lum1 by linearly interpolating this with white (when increasing the luminance) or black (otherwise) in the [XYZ] color space.
@see https://en.wikipedia.org/wiki/Relative\_luminance
example // Approximately doubling the luminance of red
example chroma.color('red').luminance(0.4) // "Vivid Tangerine" 
color.temperature(): number src
Get color temperature of this color in Kelvin. This only makes sense for colors close to those output by kelvin
example [c = chroma.color('#ff3300'), c.temperature()] [
, 943]
example [c = chroma.color('#ffe3cd'), c.temperature()] [
, 4998]
example [c = chroma.color('#b3ccff'), c.temperature()] [
, 15169]
Returns a new [Color] with a channel changed.
example chroma.color('skyblue').set('hsl.h', 0) // change hue to 0 deg (=red) 
example chroma.color('hotpink').set('lch.c', 30) // set chromaticity to 30 
example chroma.color('orangered').set('lab.l', x => x / 2) // half Lab lightness 
example chroma.color('darkseagreen').set('lch.c', x => x * 2) // double Lch saturation 
color.clipped(): boolean src
Returns whether this color is outside the RGB color cube and will be clipped/clamped when calling .rgb()
example [c = chroma.lch( 20, 40, 50), c.clipped()] [
, true]
example [c = chroma.lch( 40, 40, 50), c.clipped()] [
, false]
example [c = chroma.lch( 60, 40, 50), c.clipped()] [
, false]
example [c = chroma.lch( 80, 40, 50), c.clipped()] [
, true]
example [c = chroma.lch(100, 40, 50), c.clipped()] [
, true]
Returns black or white, whichever has the highest contrast to this. In the readme you should see the result of this.
example chroma.color('red') 
example chroma.color('yellow') 
color.alpha(): number src
Get alpha value of color.
example chroma.rgb(0, 0, 255, 0.5).alpha() 0.5
Return new [Color] with given alpha value.
example chroma.color('green').alpha(0.3) 
example chroma.color('green').alpha(0.3).hex('rgba') "#0080004d"
example chroma.color('hotpink') 
example chroma.color('hotpink').brighter() 
example chroma.color('hotpink').brighter(2) 
example chroma.color('hotpink').brighter(3) 
Returns a new [Color] with increased saturation.
example chroma.color('slategray') 
example chroma.color('slategray').saturate() 
example chroma.color('slategray').saturate(2) 
example chroma.color('slategray').saturate(3) 
Equivalent to saturate(-amount).
@see #saturate
Returns the [HSI] representation of this color. hue will always be in [0; 360). Values are never NaN.
example chroma.color('purple').hsi() [300, 1, ~0.33]
Returns the [LAB] representation of this color.
example chroma.color('purple').lab() [~29.78, ~58.93, ~-36.49]
color.num(mode: "rgb" | "rgba" | "argb" = "rgb"): number src
Return a hex-num of this color.
@see #num for a hex-number representation.
example chroma.color('yellow').alpha(0.7).hex() "#ffff00"
example chroma.color('yellow').alpha(0.7).hex('rgba') "#ffff00b3"
example chroma.color('yellow').alpha(0.7).hex('argb') "#b3ffff00"
Returns the [LCH] representation of this color. hue will always be in [0; 360). Values are never NaN.
example chroma.color('purple').lch() [~29.78, ~69.31, ~328.23]
Returns the [XYZ] representation of this color. hue will always be in [0; 360). Values are never NaN.
example chroma.color('purple').xyz() [~0.13, ~0.06, ~0.21]
Whether this Color is identical (strict equality of r, g, b, a) to color.
color.hashCode(): number src
color.toSource(): string src
example chroma.color('red').toSource() "chroma.rgb(255, 0, 0)"
example chroma.rgb(-2, 100.02, 200, 0.5).toSource() "chroma.rgb(-2, 100.02, 200, 0.5)"
color.toString(): string src
color.kelvin(): number src
example chroma.black 
example chroma.black
.cubehelix(start: number = 300, rotations: number = -1.5, hue: number | [number, number] = 1, gamma: number = 1, lightness: number | [number, number] = [0, 1]): CubeHelix src
Return a new [[CubeHelix]].
example chroma.cubehelix() // use the default helix 
example chroma.cubehelix().start(200).rotations(-0.5).gamma(0.8).lightness([0.3, 0.8]) 
Dave Green's cubehelix color scheme!
A CubeHelix is a function defined on [0, 1] which returns colors.
Dave Green's cubehelix color scheme!
A CubeHelix is a function defined on [0, 1] which returns colors.
cubehelix.start(): number src
cubehelix.start(s: number): this src
cubehelix.rotations(): number src
cubehelix.rotations(r: number): this src
cubehelix.gamma(): number src
cubehelix.gamma(g: number): this src
cubehelix.hue(): [number, number] src
cubehelix.hue(h: number | [number, number]): this src
cubehelix.lightness(): [number, number] src
cubehelix.lightness(h: number | [number, number]): this src
Convert to a [[Scale]].
example chroma.cubehelix().scale().correctLightness().domain(2, 22) 
Create a new random [Color] from a random point in the RGB color space.
.mix(col1: Chromable, col2: Chromable, f: number = 0.5, m: InterpolationMode = "rgb"): Color src
Mixes two colors. The mix ratio is a value between 0 and 1. The color mixing produces different results based the color space used for interpolation.
example chroma.mix('red', 'blue') 
example chroma.mix('red', 'blue', 0.25) 
example chroma.mix('red', 'blue', 0.75) 
example chroma.mix('red', 'blue', 0.5, 'rgb')
example chroma.mix('red', 'blue', 0.5, 'hsl') 
example chroma.mix('red', 'blue', 0.5, 'lab') 
example chroma.mix('red', 'blue', 0.5, 'lch') 
example chroma.mix('red', 'blue', 0.5, 'lrgb') 
Parse a CSS color. See MDN for all the possible variants.
example chroma.css('hsl(2rad 90% 50% / 0.9)') 
example chroma.css('laserlemon') 
example chroma.cmyk(0.2, 0.8, 0, 0) 
example chroma.color(0.2, 0.8, 0, 0, 'cmyk')
example chroma.gl(1, 1, 0, 1)
example chroma.gl([1, 0, 1, 0.5]) 
example chroma.hsl(30, 1, 0.5) 
example chroma.hsl(30, 0.6, 0.5) 
example chroma.kelvin(2000) // candle light 
example chroma.kelvin(3500) // sunset 
example chroma.kelvin(6500) // daylight 
example x0_1 => chroma.kelvin(x0_1 * 30000) // effective range: [0; 30000] 
example chroma.num(0x663399) // rebeccapurple 
example chroma.rgb(0, 100, 200) 
.average(chromables: Chromable[], mode: InterpolationMode = "rgb"): Color src
Similar to mix, but accepts more than two colors.
example colors = ['#ddd', 'yellow', 'red', 'teal'] [
, 
, 
, 
]
example chroma.average(colors) // default = 'rgb' 
example chroma.average(colors, 'lab') 
example chroma.average(colors, 'lch') 
example chroma.average(colors, 'lrgb') 
example chroma.average(['red', 'rgba(0,0,0,0.5)']).css() "rgba(128,0,0,0.75)"
example chroma.scale('black', 'red', 'gold') // linear interpolation 
example chroma.bezier('black', 'red', 'gold') // bezier interpolation 
Blends two colors using RGB channel-wise blend functions.
example chroma.blend('4CBBFC', 'EEEE22', 'multiply') 
example chroma.blend('4CBBFC', 'EEEE22', 'darken') 
example chroma.blend('4CBBFC', 'EEEE22', 'lighten') 
example scale = chroma.scale(['yellow', '008ae5']) 
example scale(0.25) 
example scale(0.5) 
example scale(0.75) 
example chroma.scale('Viridis') 
A color scale, created with scale, is a function that maps numeric values to a color palette.
The type parameter describes the output type and can be changed with out(). Defaults to Color objects.
example chroma.scale('Purples') 
example chroma.scale('Purples')(0.4) 
scale(val: number): T src
A color scale, created with scale, is a function that maps numeric values to a color palette.
The type parameter describes the output type and can be changed with out(). Defaults to Color objects.
example chroma.scale('Purples') 
example chroma.scale('Purples')(0.4)
scale.classes(): number[] src
Get the current scale classes.
scale.classes(classes: number | number[]): this src
Make the scale return a number of distint color instead of a continuous gradient. If you pass a number the scale will broken into equi-distant classes:
example chroma.scale('OrRd') // continous 
example chroma.scale('OrRd').classes(5) // equidistant classes 
example chroma.scale('OrRd').classes(8) 
example chroma.scale('OrRd').classes([0, 6, 11, 17, 20]) // also sets domain 
scale.domain(): number[] src
Get the domain.
example chroma.scale("red", "white", "blue").domain(0, 20).domain() [0, 10, 20]
scale.domain(start: number, end: number): this src
Set the domain interval on which the scale is defined. Colors are distributed equidistantly along the interval.
example chroma.scale("red", "white", "blue").domain(0, 100)(50)
example chroma.scale("red", "white", "blue").domain(0, 0.25, 1).domain(0, 100).domain() [0, 50, 100]
scale.domain(...domain: number[]): this src
Set the domain interval and the individual positions of the colors. The number of passed values must match the number of colors which define the scale. Not valid if the scale is defined by a function.
example scale = chroma.scale("red", "white", "blue").domain(0, 25, 100) 
example scale(25)
example scale(100) 
example scale(50) 
scale.mode(): InterpolationMode src
Get the interpolation mode used when calculating colors.
scale.mode(mode: InterpolationMode): this src
Set the interpolation mode used when calculating colors. The defaut mode is "rgb". See also {@link chroma#mix}
example chroma.scale("red", "green").mode("lab") 
example chroma.scale("red", "green").mode("lrgb") 
Set the output format return by this(x) and this.colors(n).
example chroma.scale("red", "white").out("hex")(0) "#ff0000"
example chroma.scale("red", "white").out("num").colors(2) [, 
]
scale.correctLightness(enableCorrectLightness: boolean = true): this src
This makes sure the lightness range is spread evenly across a color scale. Especially useful when working with multi-hue color scales, where simple gamma correction can't help you very much.
example chroma.scale('black','red','yellow','white') 
example chroma.scale('black','red','yellow','white').correctLightness() 
scale.padding(): [number, number] src
Get the padding.
scale.padding(paddingLeft: number, paddingRight: number = paddingLeft): this src
Set the padding. Positive values will "cut off" the ends of gradient, while negative values will add a section of constant color at the ends.
example chroma.scale("red", "white").padding(0.2) 
example chroma.scale("red", "white").padding(0.1)(0) 
example chroma.scale("red", "white").padding(-0.1)(0)
Get a number of equidistant colors.
example chroma.scale('OrRd').colors(5) [
, 
, 
, 
, 
]
example chroma.scale(['white', 'black']).colors(12) [, 
, 
, 
, 
, 
, 
, 
, 
, 
, 
, 
]
scale.cache(): boolean src
Get whether the cache is enabled. Defaults to true.
scale.cache(enableCache: boolean): this src
Enable or disable the cache.
scale.gamma(): number src
Get the current gamma value. Defaults to 1.
scale.gamma(gamma: number): this src
Set the gamma value. Gamma-correction can be used to "shift" a scale's center more the the beginning (gamma <
- or end (gamma > 1), typically used to "even" the lightness gradient. Default is 1.
example chroma.scale('YlGn').gamma(0.5) 
example chroma.scale('YlGn').gamma(1) 
example chroma.scale('YlGn').gamma(2) 
example chroma.scales.cool() 
example chroma.scales.hot() 
Computes the WCAG contrast ratio between two colors. A minimum contrast of 4.5:1 is recommended to ensure that text is still readable against a background color.
Compute the euclidean distance between two colors in a given color space.
example chroma.distance('#fff', '#ff0', 'rgb') 255
example chroma.distance('#fff', '#f0f', 'rgb') 255
example chroma.distance('#fff', '#ff0') ~96.95
example chroma.distance('#fff', '#f0f') ~122.16
Computes color difference as developed by the Colour Measurement Committee of the Society of Dyers and Colourists (CMC) in 1984. The implementation is adapted from Bruce Lindbloom. The parameters L and C are weighting factors for lightness and chromaticity.
example [r = '#ededee', s = '#edeeed', chroma.deltaE(r, s)] [
, 
, ~1.64]
example [r = '#ececee', s = '#eceeec', chroma.deltaE(r, s)] [
, 
, ~3.16]
example [r = '#e9e9ee', s = '#e9eee9', chroma.deltaE(r, s)] [
, 
, ~7.36]
example [r = '#e4e4ee', s = '#e4eee4', chroma.deltaE(r, s)] [
, 
, ~14.84]
example [r = '#e0e0ee', s = '#e0eee0', chroma.deltaE(r, s)] [
, 
, ~21.32]
.limits(data: number[] | DataInfo, mode: LimitsMode = "e", num: number = 7): number[] src
type InterpolationMode = "rgb" | "lab" | "hsv" | "hsi" | "hcg" | "hsl" | "lch" | "xyz" | "lrgb" | "num"
type ColorFormat = ColorMode | "hex" | "num" | "name" | "kelvin" | "css"
The original chroma-js library is released under the BSD license.
The included brewer colors are released under the Apache 2.0 license.
chroma.ts modifications are also released under the BSD license.