How to Convert Rgba to Hex Color Code Using JavaScript

Convert Hex to RGBA

//If you write your own code, remember hex color shortcuts (eg., #fff, #000)

function hexToRgbA(hex){
    var c;
    if(/^#([A-Fa-f0-9]{3}){1,2}$/.test(hex)){
        c= hex.substring(1).split('');
        if(c.length== 3){
            c= [c[0], c[0], c[1], c[1], c[2], c[2]];
        }
        c= '0x'+c.join('');
        return 'rgba('+[(c>>16)&255, (c>>8)&255, c&255].join(',')+',1)';
    }
    throw new Error('Bad Hex');
}

hexToRgbA('#fbafff')

/*  returned value: (String)
rgba(251,175,255,1)
*/

RGB to hex and hex to RGB

Note: both versions of rgbToHex expect integer values for r, g and b, so you'll need to do your own rounding if you have non-integer values.

The following will do to the RGB to hex conversion and add any required zero padding:

function componentToHex(c) {
  var hex = c.toString(16);
  return hex.length == 1 ? "0" + hex : hex;
}

function rgbToHex(r, g, b) {
  return "#" + componentToHex(r) + componentToHex(g) + componentToHex(b);
}

alert(rgbToHex(0, 51, 255)); // #0033ff

RGBA and RGB to Hex

You could make it a wrapper,and call the function based on the arguments passed

 //takes both RGB and RGBA and convert to HEX like  #000000
   // input will be string like this => rgb(0,0,0) or rgba(255,255,255, 0.5)
    function anyToHex(r, g, b, a) {
      if(a === undefined){
         return rgb2hex(r, g, b);
      }
     return rgba2hex(r, g, b, a);
    }

Getting Hex from RGBA in js

If you don't need the "a" from rgbA, tell me, I will remove its support.

But basically, you just convert every integer to hex string and add 0 if needed.

function rgbaToHex (r,g,b,a) {
  var outParts = [
    r.toString(16),
    g.toString(16),
    b.toString(16),
    Math.round(a * 255).toString(16).substring(0, 2)
  ];

  // Pad single-digit output values
  outParts.forEach(function (part, i) {
    if (part.length === 1) {
      outParts[i] = '0' + part;
    }
  })

  return ('#' + outParts.join(''));
}

alert(rgbaToHex(255,34,56,1));

How to get hex color value rather than RGB value?

var hexDigits = new Array
        ("0","1","2","3","4","5","6","7","8","9","a","b","c","d","e","f"); 

//Function to convert rgb color to hex format
function rgb2hex(rgb) {
 rgb = rgb.match(/^rgb\((\d+),\s*(\d+),\s*(\d+)\)$/);
 return "#" + hex(rgb[1]) + hex(rgb[2]) + hex(rgb[3]);
}

function hex(x) {
  return isNaN(x) ? "00" : hexDigits[(x - x % 16) / 16] + hexDigits[x % 16];
 }

(Source)

Javascript function to convert color names to hex codes

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;
}

Convert color code to hexadecimal code in javascript

Try this

const hexString = `0xff1ba5f5`const rgbaString = hexString.slice(2)console.log(rgbaString); // ff1ba5f5
const rgbaHex = hexString.match(/\w{2}/g) console.log(rgbaHex); // array of hex
const hexColor = `#${rgbaHex.slice(1,4).join("")}`;console.log(hexColor); // hex color another way
const rgba = `rgba(${rgbaHex.slice(1).map(hex => parseInt(hex,16))})`console.log(rgba); // this can actually be used in HTML

Receive incorrect alpha channel when convert rgba color to hex

Using a bitwise | (or) operator on a floating-point value does not make sense. You'll have to use ~~(achannel * 255) to get an integer value.

Depending on the range of your 0 ... 1 achannel values, you might want to use 256 instead of 255 if the value can never be 1.

edit — now that I think about it, you don't need the ~~ explicit integer conversion, because the | will do that anyway, so simply (achannel * 256) will work so long as the fractional value will always be less than 1; otherwise 255.