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Check if a string is a valid color

Published on
1 mins read

For client-side only, not work in Node.js

Simple color validator function

let isValidColor = (color) => {
  let otpNode = new Option()
  otpNode.style.color = color

  return !!otpNode.style.color
}

Usage

// Valid colors
isValidColor('purple') // true
isValidColor('burlywood') // true
isValidColor('lightsalmon') // true
isValidColor('rgb(255, 255, 255)') // true
isValidColor('rgba(255, 255, 255, .5)') // true
isValidColor('#ccc') // true
isValidColor('hsl(100, 0%, 18%)') // true

// Invalid colors
isValidColor('not-a-color-name') // false
isValidColor('dark gray') // false. Should be 'darkgray'
isValidColor('rgb(255, 255, 255, 1, 1)') // false
isValidColor('#ccczzz') // false

Caveat

Strings like unset, initial, inherit, currentcolor, transparent are also valid values, so if you want to exclude these strings, just change the function a bit:

let isValidColor = (color) => {
  let otpNode = new Option()
  otpNode.style.color = color

  return !!otpNode.style.color && !/(unset|initial|inherit|currentcolor|transparent)/i.test(color)
}

isValidColor('rgb(-1, 255, 255)') // true
isValidColor('none') // false
isValidColor('initial') // false
isValidColor('gray') // true