110

Is there a built-in function that would convert a color by name into its hex representation? Like I want to pass 'white' and receive '#FFFFFF'. I really want to avoid coding all hundred if's myself :)

0

16 Answers 16

143

No, but using the list here you could create one. Something like this:

function colourNameToHex(colour)
{
    var colours = {"aliceblue":"#f0f8ff","antiquewhite":"#faebd7","aqua":"#00ffff","aquamarine":"#7fffd4","azure":"#f0ffff",
    "beige":"#f5f5dc","bisque":"#ffe4c4","black":"#000000","blanchedalmond":"#ffebcd","blue":"#0000ff","blueviolet":"#8a2be2","brown":"#a52a2a","burlywood":"#deb887",
    "cadetblue":"#5f9ea0","chartreuse":"#7fff00","chocolate":"#d2691e","coral":"#ff7f50","cornflowerblue":"#6495ed","cornsilk":"#fff8dc","crimson":"#dc143c","cyan":"#00ffff",
    "darkblue":"#00008b","darkcyan":"#008b8b","darkgoldenrod":"#b8860b","darkgray":"#a9a9a9","darkgreen":"#006400","darkkhaki":"#bdb76b","darkmagenta":"#8b008b","darkolivegreen":"#556b2f",
    "darkorange":"#ff8c00","darkorchid":"#9932cc","darkred":"#8b0000","darksalmon":"#e9967a","darkseagreen":"#8fbc8f","darkslateblue":"#483d8b","darkslategray":"#2f4f4f","darkturquoise":"#00ced1",
    "darkviolet":"#9400d3","deeppink":"#ff1493","deepskyblue":"#00bfff","dimgray":"#696969","dodgerblue":"#1e90ff",
    "firebrick":"#b22222","floralwhite":"#fffaf0","forestgreen":"#228b22","fuchsia":"#ff00ff",
    "gainsboro":"#dcdcdc","ghostwhite":"#f8f8ff","gold":"#ffd700","goldenrod":"#daa520","gray":"#808080","green":"#008000","greenyellow":"#adff2f",
    "honeydew":"#f0fff0","hotpink":"#ff69b4",
    "indianred ":"#cd5c5c","indigo":"#4b0082","ivory":"#fffff0","khaki":"#f0e68c",
    "lavender":"#e6e6fa","lavenderblush":"#fff0f5","lawngreen":"#7cfc00","lemonchiffon":"#fffacd","lightblue":"#add8e6","lightcoral":"#f08080","lightcyan":"#e0ffff","lightgoldenrodyellow":"#fafad2",
    "lightgrey":"#d3d3d3","lightgreen":"#90ee90","lightpink":"#ffb6c1","lightsalmon":"#ffa07a","lightseagreen":"#20b2aa","lightskyblue":"#87cefa","lightslategray":"#778899","lightsteelblue":"#b0c4de",
    "lightyellow":"#ffffe0","lime":"#00ff00","limegreen":"#32cd32","linen":"#faf0e6",
    "magenta":"#ff00ff","maroon":"#800000","mediumaquamarine":"#66cdaa","mediumblue":"#0000cd","mediumorchid":"#ba55d3","mediumpurple":"#9370d8","mediumseagreen":"#3cb371","mediumslateblue":"#7b68ee",
    "mediumspringgreen":"#00fa9a","mediumturquoise":"#48d1cc","mediumvioletred":"#c71585","midnightblue":"#191970","mintcream":"#f5fffa","mistyrose":"#ffe4e1","moccasin":"#ffe4b5",
    "navajowhite":"#ffdead","navy":"#000080",
    "oldlace":"#fdf5e6","olive":"#808000","olivedrab":"#6b8e23","orange":"#ffa500","orangered":"#ff4500","orchid":"#da70d6",
    "palegoldenrod":"#eee8aa","palegreen":"#98fb98","paleturquoise":"#afeeee","palevioletred":"#d87093","papayawhip":"#ffefd5","peachpuff":"#ffdab9","peru":"#cd853f","pink":"#ffc0cb","plum":"#dda0dd","powderblue":"#b0e0e6","purple":"#800080",
    "rebeccapurple":"#663399","red":"#ff0000","rosybrown":"#bc8f8f","royalblue":"#4169e1",
    "saddlebrown":"#8b4513","salmon":"#fa8072","sandybrown":"#f4a460","seagreen":"#2e8b57","seashell":"#fff5ee","sienna":"#a0522d","silver":"#c0c0c0","skyblue":"#87ceeb","slateblue":"#6a5acd","slategray":"#708090","snow":"#fffafa","springgreen":"#00ff7f","steelblue":"#4682b4",
    "tan":"#d2b48c","teal":"#008080","thistle":"#d8bfd8","tomato":"#ff6347","turquoise":"#40e0d0",
    "violet":"#ee82ee",
    "wheat":"#f5deb3","white":"#ffffff","whitesmoke":"#f5f5f5",
    "yellow":"#ffff00","yellowgreen":"#9acd32"};

    if (typeof colours[colour.toLowerCase()] != 'undefined')
        return colours[colour.toLowerCase()];

    return false;
}
12
  • 9
    Copy / paste / search / replace
    – Greg
    Commented Oct 15, 2009 at 15:33
  • 1
    You might want to guard against inherited properties ;) colourNameToHex('constructor')
    – kangax
    Commented Oct 15, 2009 at 15:34
  • 8
    Not trying to knock the wind out of anyone's answer sails here, but as I linked to in the answer I submitted, there is a way to get HEX and RGB from named colors programatically in all browsers with \out having a gigantic table like this. Do people on Stack not read below the fold generally?
    – csuwldcat
    Commented Oct 17, 2010 at 18:45
  • 7
    For both spellings of gray, you'll also need these. The rest seem to be there based on my visual comparison. "darkgrey":"#a9a9a9", "darkslategrey":"#2f4f4f","dimgrey":"#696969","grey":"#808080","lightgray":"#d3d3d3","lightslategrey""#778899","slategrey":"#708090",
    – user984003
    Commented Feb 5, 2013 at 7:19
  • 3
    This answer is out of date (and imo manal creation of a huge array is not worth this many upvotes). A far better solution (that will not need updates any time new colors are added) is the answer from @JayB below.
    – ashleedawg
    Commented Apr 4, 2019 at 1:32
95

@dlauzon suggested I convert my comment into an answer. Thanks for suggesting! Here it is :)

function standardize_color(str){
    var ctx = document.createElement('canvas').getContext('2d');
    ctx.fillStyle = str;
    return ctx.fillStyle;
}

function standardize_color(str){
    var ctx = document.createElement("canvas").getContext("2d");
    ctx.fillStyle = str;
    return ctx.fillStyle;
}

document.getElementById("myspan1").innerHTML = standardize_color("red");
document.getElementById("myspan2").innerHTML = standardize_color("PeachPuff");
document.getElementById("myspan3").innerHTML = standardize_color("PaleGoldenRod"); 
document.getElementById("myspan4").innerHTML = standardize_color("RGB(123,234,142)"); 
document.getElementById("myspan5").innerHTML = standardize_color("HSL(284,6%,49%)");
span { font-weight:800; }
The color named "Red" has a code of: <span id="myspan1">(requires js)</span>.<br>
 ...and color "PeachPuff"'s code is: <span id="myspan2">(requires js)</span>.<br>
 ...and "PaleGoldenRod" is: <span id="myspan3">(requires js)</span>.<br><br>
 
It works with "RGB(123,234,142)" too: <span id="myspan4">(needs js)</span>  
and therefore with: "HSL(284,6%,49%)", which is: <span id="myspan5">(requires js)
</span>.  Handy!

5
  • 1
    Best answer indeed. Note that passing an invalid color will give you the default fill colour (#000000)
    – Aximili
    Commented Feb 25, 2021 at 23:06
  • What does it actually return?
    – chovy
    Commented Nov 21, 2021 at 15:02
  • 1
    This works for named colors, the rgb, hsl and hwb notations, but not for lch, oklch, lab or oklab. Does anybody know if that is intended behavior?
    – Holzchopf
    Commented Apr 6, 2023 at 12:10
  • I sometimes get back rgba(). (Google Chrome, Windows)
    – Leo
    Commented Oct 23, 2023 at 9:40
  • It won´t work if canvas is not allowed. (librefwolf)
    – theking2
    Commented Mar 30 at 16:14
68

This will give it to you in RGB - you should be able to do the hex conversion pretty easily.

d = document.createElement("div");
d.style.color = "white";
document.body.appendChild(d)
//Color in RGB 
window.getComputedStyle(d).color

Get Computed style is not supported on all browsers.

7
  • IE9+, all evergreen browsers as of this comment (2014/08/20) caniuse.com/#feat=getcomputedstyle Commented Aug 20, 2014 at 15:11
  • 10
    Note that this appends an element to your <body>; you should remove it after checking its color.
    – Nate
    Commented Dec 1, 2014 at 15:35
  • 4
    You do not even need to append the element to your document to check its style, circumventing that problem. Commented Dec 12, 2016 at 2:29
  • 6
    On Chrome, it the node does require to be in the DOM in order to get anything from getCompuedStyle. Otherwise the color attribute is "". Commented Oct 31, 2017 at 22:36
  • 3
    Can confirm the appendChild is required on Chrome. Also note: it just inherits the color from document.body if an invalid color string is provided.
    – Lea Rosema
    Commented Aug 23, 2020 at 10:43
52

Edit: I've cleaned this up a bit and made a gist and demo of it. The basic approach remains the same.

The "add an element to the DOM and check its ComputedStyle" approach seems a little complex to me — you need to add it and check it and remember to remove it and you're changing the DOM just to compute a color and does it cause reflow? So here's a solution based on a temporary (and never rendered) <canvas>:

function colorToRGBA(color) {
    // Returns the color as an array of [r, g, b, a] -- all range from 0 - 255
    // color must be a valid canvas fillStyle. This will cover most anything
    // you'd want to use.
    // Examples:
    // colorToRGBA('red')  # [255, 0, 0, 255]
    // colorToRGBA('#f00') # [255, 0, 0, 255]
    var cvs, ctx;
    cvs = document.createElement('canvas');
    cvs.height = 1;
    cvs.width = 1;
    ctx = cvs.getContext('2d');
    ctx.fillStyle = color;
    ctx.fillRect(0, 0, 1, 1);
    return ctx.getImageData(0, 0, 1, 1).data;
}

function byteToHex(num) {
    // Turns a number (0-255) into a 2-character hex number (00-ff)
    return ('0'+num.toString(16)).slice(-2);
}

function colorToHex(color) {
    // Convert any CSS color to a hex representation
    // Examples:
    // colorToHex('red')            # '#ff0000'
    // colorToHex('rgb(255, 0, 0)') # '#ff0000'
    var rgba, hex;
    rgba = colorToRGBA(color);
    hex = [0,1,2].map(
        function(idx) { return byteToHex(rgba[idx]); }
        ).join('');
    return "#"+hex;
}

Note that this lets you use anything that's a valid canvas fillStyle, so if you want to gin up a 1 pixel pattern from an image, it'll tell you the color of that as well.

I've tested this in reasonably modern versions of IE, Chrome, Safari, and Firefox.

5
  • 7
    function standardize_color(str){ var ctx = document.createElement('canvas').getContext('2d'); ctx.fillStyle = str; return ctx.fillStyle; }
    – JayB
    Commented Nov 6, 2017 at 21:02
  • 1
    That's super neat! I'm not sure if I like it better or not; with the "ctx.fillStyle normalizes colors to rbga" trick you can't put a gradient or pattern in. I guess it answers the OP in fewer lines of code but it's somewhat less flexible.
    – Nate
    Commented Nov 6, 2017 at 22:07
  • 1
    It's even per-spec: html.spec.whatwg.org/multipage/…
    – Nate
    Commented Nov 17, 2017 at 17:31
  • Thanks! Only thing that also works with oklch colors for me
    – m9t
    Commented Mar 27 at 12:52
  • It won´t work if canvas was disabled. It will be disabled for users that are aware of fingerprinting.
    – theking2
    Commented Mar 30 at 16:15
28

Here function where you use the browser to calculate it for you

function getHexColor(colorStr) {
    var a = document.createElement('div');
    a.style.color = colorStr;
    var colors = window.getComputedStyle( document.body.appendChild(a) ).color.match(/\d+/g).map(function(a){ return parseInt(a,10); });
    document.body.removeChild(a);
    return (colors.length >= 3) ? '#' + (((1 << 24) + (colors[0] << 16) + (colors[1] << 8) + colors[2]).toString(16).substr(1)) : false;
}
getHexColor('teal') // returns #008080

Explanation by line:

  • Create html element
  • Set the color
  • Get the rgb-code form the element which is just appended to the body (so it is rendered), filter numbers and convert each number to an integer.
  • Remove the html element we just created
  • Return the HEX code using zyklus code (see credits for more info)

credits to zyklus for his rgb to hex code

1
  • 1
    one liner convert from rgb(a) to #hex var colors = '#'+window.getComputedStyle(document.body.appendChild(a)).color.match(/\d+/g).map(function(a,i){ return i>2 ? '' : ('0'+parseInt(a,10).toString(16)).substr(-2); }).join('');
    – oriadam
    Commented Jun 20, 2017 at 13:04
14

Here's an all purpose solution that does exactly what you want in every browser that is 100% programmatic, goodbye giant static table of names and hex values!:

// Here is the solution tied together as a native String native extension using 
// MooTools, though you can implement the same thing in whatever framework you prefer:

(function(String){

var valueMatch = {
        'rgb(0,0,0)': { 'black': ' ', 'rgb(0,0,0)': ' ' },
        'rgba(0,0,0,0)': { 'transparent': ' ', 'rgba(0,0,0,0)': ' ' },
        '#ffffff': { 'transparent': ' ' },
        'transparent': { 'transparent': ' ' }
    },
    colorFromProbe = function(color){
        color = color.toString();
        if(!color.match(/^#.+$|^[^0-9]+$/)) return color;
        var probe = ($('moo_color_probe') || new Element('textarea', {
                'id': 'moo_color_probe',
                'styles': {
                    'display': 'none',
                    'color': 'transparent'
                }
            }).inject(document.body, 'after'));
        try{ probe.setStyle('color', color) } catch(e){ return color } //IE throws an error instead of defaulting the style to some color or transparent when the value is unrecognized
        var computed = (Browser.ie) ? ieColorToHex(probe) : (Browser.opera) ? probe.style.color : probe.getComputedStyle('color'),
            match = valueMatch[computed.replace(/ /g, '')];
        probe.setStyle('color', 'transparent');
        if((!Browser.ie || Browser.ie9) && color == 'transparent' && (match && match['transparent'])) return 'rgba(0, 0, 0, 0)';
        return (computed == 'transparent' || match && !match[color.replace(/ /g, '')]) ? color : computed;
    },
    ieColorToHex = function(probe){ // Special IE mojo, thanks to Dean Edwards for the inspiration, his code used a pop-up window to test the color, I found you can simply use a textarea instead ;)
        var value = probe.set('value', '').createTextRange().queryCommandValue("ForeColor");
        value = (((value & 0x0000ff) << 16) | (value & 0x00ff00) | ((value & 0xff0000) >>> 16)).toString(16);
        return "#000000".slice(0, 7 - value.length) + value;
    };

    String.implement({
        colorToRgb: function(){
            var color = colorFromProbe(this);
            return (color.charAt(0) == '#') ? color.hexToRgb() : color;
        },
        colorToHex: function(){
            var color = colorFromProbe(this);
            return (color.test('rgb')) ? color.rgbToHex() : color;
        }
    });

})(String);    

A more complete explanation and live example can be found here: http://www.backalleycoder.com/2010/10/05/converting-css-named-colors-to-rgb-and-hex/

8
  • 1
    +1 for the programmatic way. I couldn't use it though because this is an expensive way of resolving color and will not work smooth if I need to resolve a hundred values - for that case the "lame" lookup list works much better, though admittedly is pain in the ass to maintain :)
    – Andrey
    Commented Dec 8, 2010 at 15:38
  • 1
    Andrey, I can guarantee you that it is not even as close to as expensive as styles animations with any of the JS frameworks. With animations you are setting multiple styles thousands of times over a given period to animate a few properties of something. This is actually not unlike that type of operation, so finding values for a few hundred colors is cake, there's no noticeable performance impact.
    – csuwldcat
    Commented Dec 9, 2010 at 22:56
  • 1
    @csuwldcat: I'm far from convinced the hideous hack to make this work in IE is preferable to the big look-up table. There's definitely going to be a performance hit, and it makes it impossible to create a reverse look-up of colour names for RGB values, which can also be useful. +1 nonetheless, it hadn't occurred to me use a TextRange and queryCommandValue().
    – Tim Down
    Commented Mar 25, 2011 at 10:26
  • @csuwldcat: In a simple test on my machine, using a look-up table to resolve the colour is between 20 and 50 times faster than doing it via the DOM, depending on the browser.
    – Tim Down
    Commented Mar 25, 2011 at 11:18
  • 3
    @csuwldcat: All true, and between us we've covered the issue pretty thoroughly. I think my main point is that both approaches are valid, and that which is preferable depends on the situation, whereas your comments seem to suggest you think the programmatic solution is inherently superior.
    – Tim Down
    Commented Mar 27, 2011 at 14:58
6

You'll need to rely on getComputedStyle(...).

Example of using getComputedStyle:

function convertToHexColor(englishColor) {

    // create a temporary div. 
    var div = $('<div></div>').appendTo("body").css('background-color', englishColor);
    var computedStyle = window.getComputedStyle(div[0]);

    // get computed color.
    var computedColor = computedStyle.backgroundColor;

    // cleanup temporary div.
    div.remove();

    // done.
    return computedColor;

    // The above returns "rgb(R, G, B)" on IE9/Chrome20/Firefox13.
};

And to convert "rgb(R, G, B)" to #RRGGBB you can use:

function convertRGBDecimalToHex(rgb)
{
    var regex = /rgb *\( *([0-9]{1,3}) *, *([0-9]{1,3}) *, *([0-9]{1,3}) *\)/;
    var values = regex.exec(rgb);
    if(values.length != 4)
    {
        return rgb; // fall back to what was given.              
    }
    var r = Math.round(parseFloat(values[1]));
    var g = Math.round(parseFloat(values[2]));
    var b = Math.round(parseFloat(values[3]));
    return "#" 
        + (r + 0x10000).toString(16).substring(3).toUpperCase() 
        + (g + 0x10000).toString(16).substring(3).toUpperCase()
        + (b + 0x10000).toString(16).substring(3).toUpperCase();
}
4
  • @pimvdb Depends on how often you need to be mapping colors. You could keep the same div always in the DOM to save some time that way -- then the rest of the time spent is on two css calls (one of which probably resorts to a computed style call). Commented Nov 8, 2011 at 18:13
  • I do not believe jQuery does this, I just reviewed their source and nowhere in it does it contain a section that performs the logic needed to accomplish this. Care to include a jsFiddle link showing you setting a named color using the style object setter with jQuery and then it returning the hex?
    – csuwldcat
    Commented Jul 31, 2012 at 1:03
  • @csuwldcat Thanks for the comment. My previous code example stopped working -- I'm not sure why now it was working originally. Anyways, I have posted new code above that works, and here is a jsFiddle: jsfiddle.net/GRsCr/32. Commented Jul 31, 2012 at 4:53
  • 1
    FWIW, you don't need to convert the hex values to upper case.
    – Nate
    Commented Dec 1, 2014 at 15:43
3

building on Greg's answer including gray/gray version

added: flag to pass through unresolved strings

available as gist colorhelpersforcanvas.js

String.prototype.colorNameToHex = function (returnUnresolved) { // color list from https://stackoverflow.com/q/1573053/731179  with added gray/gray
    var hexRGB, definedColorNames = {"aliceblue": "#f0f8ff", "antiquewhite": "#faebd7", "aqua": "#00ffff", "aquamarine": "#7fffd4", "azure": "#f0ffff", "beige": "#f5f5dc", "bisque": "#ffe4c4", "black": "#000000", "blanchedalmond": "#ffebcd", "blue": "#0000ff", "blueviolet": "#8a2be2", "brown": "#a52a2a", "burlywood": "#deb887", "cadetblue": "#5f9ea0", "chartreuse": "#7fff00", "chocolate": "#d2691e", "coral": "#ff7f50", "cornflowerblue": "#6495ed", "cornsilk": "#fff8dc", "crimson": "#dc143c", "cyan": "#00ffff", "darkblue": "#00008b", "darkcyan": "#008b8b", "darkgoldenrod": "#b8860b", "darkgray": "#a9a9a9", "darkgreen": "#006400", "darkkhaki": "#bdb76b", "darkmagenta": "#8b008b", "darkolivegreen": "#556b2f", "darkorange": "#ff8c00", "darkorchid": "#9932cc", "darkred": "#8b0000", "darksalmon": "#e9967a", "darkseagreen": "#8fbc8f", "darkslateblue": "#483d8b", "darkslategray": "#2f4f4f", "darkturquoise": "#00ced1", "darkviolet": "#9400d3", "deeppink": "#ff1493", "deepskyblue": "#00bfff", "dimgray": "#696969", "dodgerblue": "#1e90ff", "firebrick": "#b22222", "floralwhite": "#fffaf0", "forestgreen": "#228b22", "fuchsia": "#ff00ff", "gainsboro": "#dcdcdc", "ghostwhite": "#f8f8ff", "gold": "#ffd700", "goldenrod": "#daa520", "gray": "#808080", "green": "#008000", "greenyellow": "#adff2f", "honeydew": "#f0fff0", "hotpink": "#ff69b4", "indianred ": "#cd5c5c", "indigo ": "#4b0082", "ivory": "#fffff0", "khaki": "#f0e68c", "lavender": "#e6e6fa", "lavenderblush": "#fff0f5", "lawngreen": "#7cfc00", "lemonchiffon": "#fffacd", "lightblue": "#add8e6", "lightcoral": "#f08080", "lightcyan": "#e0ffff", "lightgoldenrodyellow": "#fafad2", "lightgrey": "#d3d3d3", "lightgreen": "#90ee90", "lightpink": "#ffb6c1", "lightsalmon": "#ffa07a", "lightseagreen": "#20b2aa", "lightskyblue": "#87cefa", "lightslategray": "#778899", "lightsteelblue": "#b0c4de", "lightyellow": "#ffffe0", "lime": "#00ff00", "limegreen": "#32cd32", "linen": "#faf0e6", "magenta": "#ff00ff", "maroon": "#800000", "mediumaquamarine": "#66cdaa", "mediumblue": "#0000cd", "mediumorchid": "#ba55d3", "mediumpurple": "#9370d8", "mediumseagreen": "#3cb371", "mediumslateblue": "#7b68ee", "mediumspringgreen": "#00fa9a", "mediumturquoise": "#48d1cc", "mediumvioletred": "#c71585", "midnightblue": "#191970", "mintcream": "#f5fffa", "mistyrose": "#ffe4e1", "moccasin": "#ffe4b5", "navajowhite": "#ffdead", "navy": "#000080", "oldlace": "#fdf5e6", "olive": "#808000", "olivedrab": "#6b8e23", "orange": "#ffa500", "orangered": "#ff4500", "orchid": "#da70d6", "palegoldenrod": "#eee8aa", "palegreen": "#98fb98", "paleturquoise": "#afeeee", "palevioletred": "#d87093", "papayawhip": "#ffefd5", "peachpuff": "#ffdab9", "peru": "#cd853f", "pink": "#ffc0cb", "plum": "#dda0dd", "powderblue": "#b0e0e6", "purple": "#800080", "red": "#ff0000", "rosybrown": "#bc8f8f", "royalblue": "#4169e1", "saddlebrown": "#8b4513", "salmon": "#fa8072", "sandybrown": "#f4a460", "seagreen": "#2e8b57", "seashell": "#fff5ee", "sienna": "#a0522d", "silver": "#c0c0c0", "skyblue": "#87ceeb", "slateblue": "#6a5acd", "slategray": "#708090", "snow": "#fffafa", "springgreen": "#00ff7f", "steelblue": "#4682b4", "tan": "#d2b48c", "teal": "#008080", "thistle": "#d8bfd8", "tomato": "#ff6347", "turquoise": "#40e0d0", "violet": "#ee82ee", "wheat": "#f5deb3", "white": "#ffffff", "whitesmoke": "#f5f5f5", "yellow": "#ffff00", "yellowgreen": "#9acd32", "darkgrey": "#a9a9a9", "darkslategrey": "#2f4f4f", "dimgrey": "#696969", "grey": "#808080", "lightgray": "#d3d3d3", "lightslategrey": "#778899", "slategrey": "#708090"};
    if (definedColorNames[this.toLowerCase()] !== undefined) {
        hexRGB = definedColorNames[this.toLowerCase()];
        // to keep unresolved strings set flag returnUnresolved to true
    } else {if (returnUnresolved) {hexRGB = this; } else {hexRGB = undefined; } }
    return hexRGB;
};

some test cases:

console.log("black".colorNameToHex());                //returns #000000
console.log("rgba(100,100,0,0.7)".colorNameToHex());  //returns undefined 
console.log("rgba(100,100,0,0.7)".colorNameToHex(1)); //returns rgba(100,100,0,0.7) 

as a bonus here my use case for that in a color-string to color-string-with-alpha conversion:

works with any css defined color including: rgba, rgb, r%g%b%, #rgb, #rrggbb, hsl, hsla

mostly useful in drawing with alpha/opacity/transparency onto a HTML5 canvas element with passed on color strings

String.prototype.setAlpha = function (alpha) {
    // change alpha of color string in any css color space
    // intended for use in canvas/svg
    // currently implemented:
    // css defined colors               > rgba
    // rgba, rgb, r%g%b%, #rgb, #rrggbb > rgba
    // hsl, hsla                        > hsla
    // unresolved                       > as is
    //
    // If no alpha is passed its is set to 1 or keeps the value in rgba/hsla

    // kill whitespace split at "(", ")", ","
    var i, hex, c = this.replace(/\s/g, '').split(/[\(\),]/);
    function extractHex(string) {
        if (string.charAt(0) === "#") {  // detect hex strings
            hex = string.replace(/#/g, '');
            string = "hex";
        } else {hex = undefined; }
        return string;
    }
    extractHex(c[0]);
    if (["rgba", "rgb", "hsla", "hsl", "hex"].indexOf(c[0]) === -1) {
        c[0] = extractHex(c[0].colorNameToHex(1)); // detect defined color names
    }
    switch (c[0]) {
    case "rgba":
        if (alpha === undefined) {alpha = c[4]; }
        c = "rgba(" + c[1] + ", " + c[2] + ", " + c[3] + ", " + alpha + ")";
        break;
    case "rgb":
        if (alpha === undefined) {alpha = 1; }
        //  if colors are in percentage values
        for  (i = 1; i <= 3; i = i + 1) {
            if (c[i].charAt(c[i].length - 1) === "%") {
                c[i] = Math.round(c[i].replace(/%/g, '') * 2.55);
            }
        }
        c = "rgba(" + c[1] + ", " + c[2] + ", " + c[3] + ", " + alpha + ")";
        break;
    case "hsl":
        if (alpha === undefined) {alpha = 1; }
        c = "hsla(" + c[1] + ", " + c[2] + ", " + c[3] + ", " + alpha + ")";
        break;
    case "hsla":
        if (alpha === undefined) {alpha = c[4]; }
        c = "hsla(" + c[1] + ", " + c[2] + ", " + c[3] + ", " + alpha + ")";
        break;
    case "hex":
        if (alpha === undefined) {alpha = 1; }
        if (hex.length === 3) {
            c[1] = parseInt(hex.charAt(0) + hex.charAt(0), 16);
            c[2] = parseInt(hex.charAt(1) + hex.charAt(1), 16);
            c[3] = parseInt(hex.charAt(2) + hex.charAt(2), 16);
        } else if (hex.length === 6) {
            c[1] = parseInt(hex.charAt(0) + hex.charAt(1), 16);
            c[2] = parseInt(hex.charAt(2) + hex.charAt(3), 16);
            c[3] = parseInt(hex.charAt(4) + hex.charAt(5), 16);
        } else {break; }
        c = "rgba(" + c[1] + ", " + c[2] + ", " + c[3] + ", " + alpha + ")";
        break;
    default: c = this; break;
    }
    return c;
};

test:

console.log("orange".setAlpha(0.3));
1
  • Please do not extend primitive objects because it greatly reduces performance everywhere.
    – Jack G
    Commented Apr 28, 2018 at 20:28
3

Download & include the w3color.js from w3school.

then in your script you can use any of the following functions:

let c = w3color("violet");
c.darker(n)
c.desaturate(n)
c.isDark(n)
c.lighter(n)
c.saturate(n)
c.toCmyk()
c.toCmykString()
c.toCmykStringDecimal()
c.toHexString()
c.toHsl()
c.toHslString()
c.toHslStringDecimal()
c.toHslaString()
c.toHwb()
c.toHwbString()
c.toHwbStringDecimal()
c.toHwbaString()
c.toName()
c.toNcol()
c.toNcolString()
c.toNcolStringDecimal()
c.toNcolaString()
c.toRgb()
c.toRgbString()
c.toRgbaString()
2

Run the snippet to see how easily "any" valid CSS color (HSL, names, hex, system colors*, etc.) can be converted to R/G/B values using any element you happen to have laying around.

*Enter a value of background and you'll get your Windows Desktop background color (in Firefox, anyways).

go();
function go() {
  clr.style.backgroundColor = document.getElementById('txt').value;
  document.getElementById('rgb').innerHTML = window.getComputedStyle(clr).backgroundColor;
}
* { margin:0; box-sizing:border-box; font-family:verdana; overflow:hidden; }
#txt,#rgb,#clr { height:30vh; width:97vw; padding:5vmin; margin:2vmin; font-size:13vh; border:1vmin solid; text-align:center; vertical-align:middle;}
#txt{margin-bottom:0;}
<input type='text' id='txt' onkeyup='go()' value='chartreuse' placeholder='Enter any css color . . .' autofocus>
<div id='clr'></div>
<div id='rgb'></div>

1

The solution from Ties converted to TypeScript:

export const getHexColorFromLiteral = (
  colorStr:
    | 'aliceblue'
    | 'antiquewhite'
    | 'aqua'
    | 'aquamarine'
    | 'azure'
    | 'beige'
    | 'bisque'
    | 'black'
    | 'blanchedalmond'
    | 'blue'
    | 'blueviolet'
    | 'brown'
    | 'burlywood'
    | 'cadetblue'
    | 'chartreuse'
    | 'chocolate'
    | 'coral'
    | 'cornflowerblue'
    | 'cornsilk'
    | 'crimson'
    | 'cyan'
    | 'darkblue'
    | 'darkcyan'
    | 'darkgoldenrod'
    | 'darkgray'
    | 'darkgreen'
    | 'darkkhaki'
    | 'darkmagenta'
    | 'darkolivegreen'
    | 'darkorange'
    | 'darkorchid'
    | 'darkred'
    | 'darksalmon'
    | 'darkseagreen'
    | 'darkslateblue'
    | 'darkslategray'
    | 'darkturquoise'
    | 'darkviolet'
    | 'deeppink'
    | 'deepskyblue'
    | 'dimgray'
    | 'dodgerblue'
    | 'firebrick'
    | 'floralwhite'
    | 'forestgreen'
    | 'fuchsia'
    | 'gainsboro'
    | 'ghostwhite'
    | 'gold'
    | 'goldenrod'
    | 'gray'
    | 'green'
    | 'greenyellow'
    | 'honeydew'
    | 'hotpink'
    | 'indianred'
    | 'indigo'
    | 'ivory'
    | 'khaki'
    | 'lavender'
    | 'lavenderblush'
    | 'lawngreen'
    | 'lemonchiffon'
    | 'lightblue'
    | 'lightcoral'
    | 'lightcyan'
    | 'lightgoldenrodyellow'
    | 'lightgray'
    | 'lightgreen'
    | 'lightpink'
    | 'lightsalmon'
    | 'lightseagreen'
    | 'lightskyblue'
    | 'lightslategray'
    | 'lightsteelblue'
    | 'lightyellow'
    | 'lime'
    | 'limegreen'
    | 'linen'
    | 'magenta'
    | 'maroon'
    | 'mediumaquamarine'
    | 'mediumblue'
    | 'mediumorchid'
    | 'mediumpurple'
    | 'mediumseagreen'
    | 'mediumslateblue'
    | 'mediumspringgreen'
    | 'mediumturquoise'
    | 'mediumvioletred'
    | 'midnightblue'
    | 'mintcream'
    | 'mistyrose'
    | 'moccasin'
    | 'navajowhite'
    | 'navy'
    | 'oldlace'
    | 'olive'
    | 'olivedrab'
    | 'orange'
    | 'orangered'
    | 'orchid'
    | 'palegoldenrod'
    | 'palegreen'
    | 'paleturquoise'
    | 'palevioletred'
    | 'papayawhip'
    | 'peachpuff'
    | 'peru'
    | 'pink'
    | 'plum'
    | 'powderblue'
    | 'purple'
    | 'rebeccapurple'
    | 'red'
    | 'rosybrown'
    | 'royalblue'
    | 'saddlebrown'
    | 'salmon'
    | 'sandybrown'
    | 'seagreen'
    | 'seashell'
    | 'sienna'
    | 'silver'
    | 'skyblue'
    | 'slateblue'
    | 'slategray'
    | 'snow'
    | 'springgreen'
    | 'steelblue'
    | 'tan'
    | 'teal'
    | 'thistle'
    | 'tomato'
    | 'turquoise'
    | 'violet'
    | 'wheat'
    | 'white'
    | 'whitesmoke'
    | 'yellow'
    | 'yellowgreen'
) => {
    const div = document.createElement('div')
    div.style.color = colorStr
    document.body.appendChild(div)

    const computedColor = window.getComputedStyle(div).color
    const matchResult = computedColor.match(/\d+/g)
    if (matchResult !== null) {
        const colors = matchResult.map((a) => parseInt(a, 10))

        document.body.removeChild(div)
        return colors.length >= 3
            ? '#' + ((1 << 24) + (colors[0] << 16) + (colors[1] << 8) + colors[2]).toString(16).substr(1)
            : false
    }

    return false
}
0

Not that's built-in, as far as I know. It would be kind of a hack, but I think you could create an invisible div, set its CSS background property to the named color, then use JS to get the background color of the div, then delete the div.

2
  • Where is the guarantee that computed color value will be represented as hex?
    – kangax
    Commented Oct 15, 2009 at 15:30
  • @kangax: JS would give you the color. how you want to represent it is up to you.
    – Kip
    Commented Oct 15, 2009 at 16:01
0

IE8 getComputedStyle polyfill if needed

var rgbToHex = function(r, g, b) {
    return "#" + (16777216 | b | (g << 8) | (r << 16)).toString(16).slice(1);
};

var d = document.createElement('div');
d.style.color = 'white';
window.document.body.appendChild(d);
var parts = (window.getComputedStyle(d).color || '').match(/\d+/g);
var f = function(n) { return parseInt(n, 10); };
window.document.body.removeChild(d);
var hex = rgbToHex(f(parts[0]), f(parts[1]), f(parts[2]));

//"#ffffff"
0

This function request a named color and send return a hexadecimal color value. If the named color not supported (example "whyte") send back black color by default but on consol you can find a warning: Not supported named color: ${namedColor}

const namedColorToHex = namedColor => {
    const html = document.querySelector("html");
    const originalColor = html.style.color;
    html.style.color = namedColor;
    const rgbFormatBgColor = window.getComputedStyle(html).color;
    if (namedColor !== "black" && rgbFormatBgColor === "rgb(0, 0, 0)") {
        console.warn(`Not supported named color: ${namedColor}`);
    }
    html.style.color = originalColor;
    const regEx = /(\d+)/g;
    const result = rgbFormatBgColor.match(regEx);
    let hexColor = `#`;
    result.forEach(value => {
        let hex = Number(value).toString(16);
        if (hex.length === 1) {
            hex = `0${hex}`;
        }
        hexColor += hex;
    });
    return hexColor;
};
0

With Firefox 94 you get the rgb color when formated with a color name. But you have to inject the dummy element at first to the page.

// Vanilla and jQuery

console.clear();

var 
  colors = ['cyan', 'magenta', 'yellow']
  dummy     = {},
  colorObj  = {},
  rgbString = '',
  rgb2hex   = function(rgb) {
    rgb = rgb.match(/^rgba?[\s+]?\([\s+]?(\d+)[\s+]?,[\s+]?(\d+)[\s+]?,[\s+]?(\d+)[\s+]?/i);
    return (rgb && rgb.length === 4) ? "#" +
    ("0" + parseInt(rgb[1],10).toString(16)).slice(-2) +
    ("0" + parseInt(rgb[2],10).toString(16)).slice(-2) +
    ("0" + parseInt(rgb[3],10).toString(16)).slice(-2) : '';
  }
;

$(colors).each(function(i, color) {
  dummy = $('<b style="background-color:' + color + '"></b>');
  // inject the dummy
  $('body').append(dummy);
  // get the rgb color 
  rgbString = dummy.css('background-color');
  // build an object with 'color name', 'rgb color' and 'hex color'
  colorObj[i] = [color, rgbString, rgb2hex(rgbString)]; 
  // delete the dummy 
  dummy.remove();  
});

console.dir(colorObj);

If you need an array with all 140 color names

colors = [
  'aliceblue',
  'antiquewhite',
  'aqua',
  'aquamarine',
  'azure',
  'beige',
  'bisque',
  'black',
  'blanchedalmond',
  'blue',
  'blueviolet',
  'brown',
  'burlywood',
  'cadetblue',
  'chartreuse',
  'chocolate',
  'coral',
  'cornflowerblue',
  'cornsilk',
  'crimson',
  'cyan',
  'darkblue',
  'darkcyan',
  'darkgoldenrod',
  'darkgray',
  'darkgreen',
  'darkkhaki',
  'darkmagenta',
  'darkolivegreen',
  'darkorange',
  'darkorchid',
  'darkred',
  'darksalmon',
  'darkseagreen',
  'darkslateblue',
  'darkslategray',
  'darkturquoise',
  'darkviolet',
  'deeppink',
  'deepskyblue',
  'dimgray',
  'dodgerblue',
  'firebrick',
  'floralwhite',
  'forestgreen',
  'fuchsia',
  'gainsboro',
  'ghostwhite',
  'gold',
  'goldenrod',
  'gray',
  'green',
  'greenyellow',
  'honeydew',
  'hotpink',
  'indianred',
  'indigo',
  'ivory',
  'khaki',
  'lavender',
  'lavenderblush',
  'lawngreen',
  'lemonchiffon',
  'lightblue',
  'lightcoral',
  'lightcyan',
  'lightgoldenrodyellow',
  'lightgray',
  'lightgreen',
  'lightpink',
  'lightsalmon',
  'lightseagreen',
  'lightskyblue',
  'lightslategray',
  'lightsteelblue',
  'lightyellow',
  'lime',
  'limegreen',
  'linen',
  'magenta',
  'maroon',
  'mediumaquamarine',
  'mediumblue',
  'mediumorchid',
  'mediumpurple',
  'mediumseagreen',
  'mediumslateblue',
  'mediumspringgreen',
  'mediumturquoise',
  'mediumvioletred',
  'midnightblue',
  'mintcream',
  'mistyrose',
  'moccasin',
  'navajowhite',
  'navy',
  'oldlace',
  'olive',
  'olivedrab',
  'orange',
  'orangered',
  'orchid',
  'palegoldenrod',
  'palegreen',
  'paleturquoise',
  'palevioletred',
  'papayawhip',
  'peachpuff',
  'peru',
  'pink',
  'plum',
  'powderblue',
  'purple',
  'red',
  'rosybrown',
  'royalblue',
  'saddlebrown',
  'salmon',
  'sandybrown',
  'seagreen',
  'seashell',
  'sienna',
  'silver',
  'skyblue',
  'slateblue',
  'slategray',
  'snow',
  'springgreen',
  'steelblue',
  'tan',
  'teal',
  'thistle',
  'tomato',
  'turquoise',
  'violet',
  'wheat',
  'white',
  'whitesmoke',
  'yellow',
  'yellowgreen'
]
-3

Quick code for HEX / RGB values only, might be useful to someone, and can be adapted to include names: pull the whole object in the for loop, check the name and if it matches you've got your hex / rbg. They are taken from here: http://www.colourlovers.com/web/blog/2008/04/22/all-120-crayon-names-color-codes-and-fun-facts

Most importantly, please notice the correct spelling of "colour" :P

/*COLOURS*/
function loadColourPalette() {

$("#colourPalette").empty();
//load them animated
for (var t = 0; t<120; t++){
    var c = returnColourForIndex(t);
    console.log("c is " + c);
    var div = '<div class="colourBox" id="cb'+t+'" style="background:'+c+'"></div>';
    $("#colourPalette").append(div);
}

}



function returnColourForIndex(i){

var colours = [     {hex:"CD4A4A",rgb:"205,74,74"},
                    {hex:"CC6666",rgb:"204,102,102"},
                    {hex:"BC5D58",rgb:"188,93,88"},
                    {hex:"FF5349",rgb:"255,83,73"},
                    {hex:"FD5E53",rgb:"253,94,83"},
                    {hex:"FD7C6E",rgb:"253,124,110"},
                    {hex:"FDBCB4",rgb:"253,188,180"},
                    {hex:"FF6E4A",rgb:"255,110,74"},
                    {hex:"FFA089",rgb:"255,160,137"},
                    {hex:"EA7E5D",rgb:"234,126,93"},
                    {hex:"B4674D",rgb:"180,103,77"},
                    {hex:"A5694F",rgb:"165,105,79"},
                    {hex:"FF7538",rgb:"255,117,56"},
                    {hex:"FF7F49",rgb:"255,127,73"},
                    {hex:"DD9475",rgb:"221,148,117"},
                    {hex:"FF8243",rgb:"255,130,67"},
                    {hex:"FFA474",rgb:"255,164,116"},
                    {hex:"9F8170",rgb:"159,129,112"},
                    {hex:"CD9575",rgb:"205,149,117"},
                    {hex:"EFCDB8",rgb:"239,205,184"},
                    {hex:"D68A59",rgb:"214,138,89"},
                    {hex:"DEAA88",rgb:"222,170,136"},
                    {hex:"FAA76C",rgb:"250,167,108"},
                    {hex:"FFCFAB",rgb:"255,207,171"},
                    {hex:"FFBD88",rgb:"255,189,136"},
                    {hex:"FDD9B5",rgb:"253,217,181"},
                    {hex:"FFA343",rgb:"255,163,67"},
                    {hex:"EFDBC5",rgb:"239,219,197"},
                    {hex:"FFB653",rgb:"255,182,83"},
                    {hex:"E7C697",rgb:"231,198,151"},
                    {hex:"8A795D",rgb:"138,121,93"},
                    {hex:"FAE7B5",rgb:"250,231,181"},
                    {hex:"FFCF48",rgb:"255,207,72"},
                    {hex:"FCD975",rgb:"252,217,117"},
                    {hex:"FDDB6D",rgb:"253,219,109"},
                    {hex:"FCE883",rgb:"252,232,131"},
                    {hex:"F0E891",rgb:"240,232,145"},
                    {hex:"ECEABE",rgb:"236,234,190"},
                    {hex:"BAB86C",rgb:"186,184,108"},
                    {hex:"FDFC74",rgb:"253,252,116"},
                    {hex:"FFFF99",rgb:"255,255,153"},
                    {hex:"C5E384",rgb:"197,227,132"},
                    {hex:"B2EC5D",rgb:"178,236,93"},
                    {hex:"87A96B",rgb:"135,169,107"},
                    {hex:"A8E4A0",rgb:"168,228,160"},
                    {hex:"1DF914",rgb:"29,249,20"},
                    {hex:"76FF7A",rgb:"118,255,122"},
                    {hex:"71BC78",rgb:"113,188,120"},
                    {hex:"6DAE81",rgb:"109,174,129"},
                    {hex:"9FE2BF",rgb:"159,226,191"},
                    {hex:"1CAC78",rgb:"28,172,120"},
                    {hex:"30BA8F",rgb:"48,186,143"},
                    {hex:"45CEA2",rgb:"69,206,162"},
                    {hex:"3BB08F",rgb:"59,176,143"},
                    {hex:"1CD3A2",rgb:"28,211,162"},
                    {hex:"17806D",rgb:"23,128,109"},
                    {hex:"158078",rgb:"21,128,120"},
                    {hex:"1FCECB",rgb:"31,206,203"},
                    {hex:"78DBE2",rgb:"120,219,226"},
                    {hex:"77DDE7",rgb:"119,221,231"},
                    {hex:"80DAEB",rgb:"128,218,235"},
                    {hex:"199EBD",rgb:"251,58,189"},
                    {hex:"1CA9C9",rgb:"28,169,201"},
                    {hex:"1DACD6",rgb:"291,72,214"},
                    {hex:"9ACEEB",rgb:"154,206,235"},
                    {hex:"1A4876",rgb:"26,72,118"},
                    {hex:"1974D2",rgb:"25,116,210"},
                    {hex:"2B6CC4",rgb:"43,108,196"},
                    {hex:"1F75FE",rgb:"31,117,254"},
                    {hex:"C5D0E6",rgb:"197,208,230"},
                    {hex:"B0B7C6",rgb:"176,183,198"},
                    {hex:"5D76CB",rgb:"93,118,203"},
                    {hex:"A2ADD0",rgb:"162,173,208"},
                    {hex:"979AAA",rgb:"151,154,170"},
                    {hex:"ADADD6",rgb:"173,173,214"},
                    {hex:"7366BD",rgb:"115,102,189"},
                    {hex:"7442C8",rgb:"116,66,200"},
                    {hex:"7851A9",rgb:"120,81,169"},
                    {hex:"9D81BA",rgb:"157,129,186"},
                    {hex:"926EAE",rgb:"146,110,174"},
                    {hex:"CDA4DE",rgb:"205,164,222"},
                    {hex:"8F509D",rgb:"143,80,157"},
                    {hex:"C364C5",rgb:"195,100,197"},
                    {hex:"FB7EFD",rgb:"251,126,253"},
                    {hex:"FC74FD",rgb:"252,116,253"},
                    {hex:"8E4585",rgb:"142,69,133"},
                    {hex:"FF1DCE",rgb:"255,29,206"},
                    {hex:"FF48D0",rgb:"255,72,208"},
                    {hex:"E6A8D7",rgb:"230,168,215"},
                    {hex:"C0448F",rgb:"192,68,143"},
                    {hex:"6E5160",rgb:"110,81,96"},
                    {hex:"DD4492",rgb:"221,68,146"},
                    {hex:"FF43A4",rgb:"255,67,164"},
                    {hex:"F664AF",rgb:"246,100,175"},
                    {hex:"FCB4D5",rgb:"252,180,213"},
                    {hex:"FFBCD9",rgb:"255,188,217"},
                    {hex:"F75394",rgb:"247,83,148"},
                    {hex:"FFAACC",rgb:"255,170,204"},
                    {hex:"E3256B",rgb:"227,37,107"},
                    {hex:"FDD7E4",rgb:"253,215,228"},
                    {hex:"CA3767",rgb:"202,55,103"},
                    {hex:"DE5D83",rgb:"222,93,131"},
                    {hex:"FC89AC",rgb:"252,137,172"},
                    {hex:"F780A1",rgb:"247,128,161"},
                    {hex:"C8385A",rgb:"200,56,90"},
                    {hex:"EE204D",rgb:"238,32,77"},
                    {hex:"FF496C",rgb:"255,73,108"},
                    {hex:"EF98AA",rgb:"239,152,170"},
                    {hex:"FC6C85",rgb:"252,108,133"},
                    {hex:"FC2847",rgb:"252,40,71"},
                    {hex:"FF9BAA",rgb:"255,155,170"},
                    {hex:"CB4154",rgb:"203,65,84"},
                    {hex:"FFFFFF",rgb:"255,255,255"},
                    {hex:"EDEDED",rgb:"237,237,237"},
                    {hex:"DBD7D2",rgb:"219,215,210"},
                    {hex:"CDC5C2",rgb:"205,197,194"},
                    {hex:"95918C",rgb:"149,145,140"},
                    {hex:"414A4C",rgb:"65,74,76"},
                    {hex:"232323",rgb:"35,35,35"},
                    {hex:"000000",rgb:"0,0,0"}];

return "#"+colours[i].hex;

}
1
  • Colour v.s. color depends on British v.s. English spelling. Therefore, color is just as right as colour as it depends on which country you are in. Also, I don't see the purpose of this at all. Why not function hexToRGB(hex){return hex.split(/(?=(?:..)*$)/g).map(function(x){return parseInt(x,16)}).join(",")}
    – Jack G
    Commented Apr 28, 2018 at 20:33

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