colorjs.io

What is colorjs.io?

colorjs.io is a comprehensive library for color manipulation and conversion. It supports a wide range of color spaces and provides utilities for color mixing, contrast checking, and more.

What are colorjs.io's main functionalities?

Color Conversion

This feature allows you to convert colors between different color spaces. In the example, the color 'red' is converted to the LCH color space.

const Color = require('colorjs.io');
const color = new Color('red');
console.log(color.to('lch').toString());

Color Manipulation

This feature allows you to manipulate colors, such as lightening or darkening them. In the example, the color 'blue' is lightened by 20%.

const Color = require('colorjs.io');
const color = new Color('blue');
const lighterColor = color.lighten(0.2);
console.log(lighterColor.toString());

Color Mixing

This feature allows you to mix two colors together. In the example, 'red' and 'blue' are mixed in equal parts to create a new color.

const Color = require('colorjs.io');
const color1 = new Color('red');
const color2 = new Color('blue');
const mixedColor = color1.mix(color2, 0.5);
console.log(mixedColor.toString());

Contrast Checking

This feature allows you to check the contrast ratio between two colors. In the example, the contrast ratio between 'white' and 'black' is calculated.

const Color = require('colorjs.io');
const color1 = new Color('white');
const color2 = new Color('black');
console.log(color1.contrast(color2));

Other packages similar to colorjs.io

color

The 'color' package is a popular library for color manipulation and conversion. It supports a variety of color spaces and provides methods for color transformations. Compared to colorjs.io, it has a simpler API but fewer features.

chroma-js

chroma-js is another powerful library for color manipulation and conversion. It offers a wide range of color spaces and provides utilities for color scales and interpolation. Compared to colorjs.io, chroma-js is more focused on color scales and data visualization.

tinycolor2

tinycolor2 is a lightweight library for color manipulation and conversion. It supports basic color transformations and provides a simple API. Compared to colorjs.io, tinycolor2 is less feature-rich but more lightweight and easier to use for simple tasks.

README

Color.js: Let’s get serious about color

Official website • Contribution guide

Color.js is a color conversion and modification library originally created by two of the editors of the CSS Color specifications: Lea Verou and Chris Lilley. They continue to work on it, but are also joined by an exceptional small grassroots team of co-maintainers.

Features

• Color space agnostic: Each color object is basically a list of coords and a color space reference. Operations are color space agnostic. Modules for a wide variety of color spaces, including Lab/LCh, OKLab/OKLCh, sRGB and friends (HSL/HSV/HWB), Display P3, J_za_zb_z, REC.2100 and many more.
• Doesn't gloss over color science: Actual gamut mapping instead of naïve clipping, multiple DeltaE methods (76, CMC, 2000, J_z), multiple chromatic adaptation methods (von Kries, Bradford, CAT02, CAT16), all with sensible defaults
• Up to date with CSS Color 4: Every CSS Color 4 format & color space supported for both input and output, whether your browser supports it or not.
• Readable, object-oriented API: Color objects for multiple operations on the same color, and static Color.something() functions for one-off calculations
• Modular & Extensible: Use only what you need, or a bundle. Client-side or Node. Deep extensibility with hooks.
• Fast & efficient: Procedural, tree-shakeable API available for performance sensitive tasks and reduced bundle size

Impact

• Has been used to create demos for several W3C specifications
• Has been used by browsers to test their CSS Color 4/5 implementations
• Over 2 million total npm downloads!
• Used by several high impact projects, including Sass, Open Props, axe accessibility testing engine, and OddContrast and CSS HD Gradients color tools
• Parts of Color.js’s API are used as a testing ground for the design of a native Color object for the Web platform.

Installation

Color.js is designed make simple things easy, and complex things possible, and that extends to installation as well.

For quick experiments, you can just import Color.js directly from the CDN (kindly provided by the awesome folks at Netlify) with all modules included:

import Color from "https://colorjs.io/dist/color.js";

You can also install via npm if you’d prefer:

npm install colorjs.io

Whether you’re using NPM, the CDN, or local files, Color.js allows you to also import specific modules by directly importing from src:

• https://colorjs.io/src/ for the CDN
• `node_modules/colorjs.io/src/ for NPM

For example:

import Color from "https://colorjs.io/src/color.js";
import p3 from "https://colorjs.io/src/spaces/p3.js";
import rec2020 from "https://colorjs.io/src/spaces/rec2020.js";
import deltaE200 from "https://colorjs.io/src/deltaE/deltaE2000.js";

Warning: To use import statements in a browser, your <script> needs type="module"

Are you old school and prefer to simply have a global Color variable? We’ve got you covered! Just include the following script in your HTML:

<script src="https://colorjs.io/dist/color.global.js"></script>

Read more about installation

Reading colors

Any color from CSS Color Level 4 should work:

let color = new Color("slategray");
let color2 = new Color("hwb(60 30% 40% / .5)");
let color3 = new Color("color(display-p3 0 1 0 / .9)");
let color4 = new Color("lch(50% 80 30)");

You can also create Color objects manually:

let color2 = new Color("hwb", [60, 30, 40], .5);
let color3 = new Color({space: "p3", coords: [0, 1, 0], alpha: .9});

Read more about color objects

Manipulating colors

You can use properties to modify coordinates of any color space and convert back

let color = new Color("slategray");
color.lch.l = 80; // Set coord directly in any color space
color.lch.c *= 1.2; // saturate by increasing LCH chroma by 20%
color.hwb.w += 10; // any other color space also available

To modify coordinates in any color space you use color.set() and color.setAll():

let color = new Color("slategray");

// Multiple coordinates
color.set({
	"lch.l": 80, // set lightness to 80
	"lch.c": c => c * 1.2 // Relative manipulation
});

// Set single coordinate
color.set("hwb.w", w => w + 10);

Coordinates of the color's color space are available without a prefix:

let color = new Color("slategray").to("lch");

// Multiple coordinates
color.set({
	l: 80, // set lightness to 80
	c: c => c * 1.2 // Relative manipulation
});

// Set single coordinate
color.set("h", 30);

Chaining-style modifications are also supported:

let color = new Color("lch(50% 50 10)");
color = color.set({
	h: h => h + 180,
	c: 60
}).lighten();

You can also use properties:

let color = new Color("slategray");
color.lch.l = 80; // Set coord directly in any color space
color.lch.c *= 1.2; // saturate by increasing LCH chroma by 20%
color.hwb.w += 10; // any other color space also available

Coordinates of the color's color space are available without a prefix:

let color = new Color("slategray").to("lch");
color.l = 80; // Set LCH lightness
color.c *= 1.2; // saturate by increasing LCH chroma

Read more about color manipulation

Converting between color spaces & stringifying

Convert to any color space:

let color = new Color("slategray");
color.to("lch") // Convert to LCH

Output in any color space

let color = new Color("slategray");
color + ""; // default stringification
color.to("p3").toString({precision: 3});

Clip to gamut or don't

let color = new Color("p3", [0, 1, 0]);
color.to("srgb") + ""; // Default toString()
color.to("srgb").toString({inGamut: false});

Read more about output

Interpolation

Get a function that accepts a percentage:

let color = new Color("p3", [0, 1, 0]);
let redgreen = color.range("red", {
	space: "lch", // interpolation space
	outputSpace: "srgb"
});
redgreen(.5); // midpoint

Interpolation by discrete steps:

let color = new Color("p3", [0, 1, 0]);
color.steps("red", {
	space: "lch",
	outputSpace: "srgb",
	maxDeltaE: 3, // max deltaE between consecutive steps
	steps: 10 // min number of steps
});

Shortcut for specific points in the range:

let color = new Color("p3", [0, 1, 0]);
let redgreen = color.mix("red", .5, {space: "lch", outputSpace: "srgb"});
let reddishGreen = color.mix("red", .25, {space: "lch", outputSpace: "srgb"});

Static syntax (every color method has a static one too):

Color.mix("color(display-p3 0 1 0)", "red", .5);

Read more about interpolation