Letter Avatars : https://codepen.io/arturheinze/pen/ZGvOMw

index.html

<h1>Letter Avatars</h1>

<small><strong>Usage:</strong></small>
<pre>
<code>&lt;img width=&quot;60&quot; height=&quot;60&quot; avatar=&quot;Andy Dandy&quot;&gt;</code>
</pre>

    <div>
        <img width="60" height="60" avatar="Andy Dandy">
        <img class="round" width="60" height="60" avatar="Andy Dandy">
        <img width="30" height="30" avatar="Andy">
        <img class="round" width="30" height="30" avatar="Andy">
    </div>

    <div>
        <img width="60" height="60" avatar="Bernhard Golf">
    </div>

    <div>
        <img width="60" height="60" avatar="Carsten Muller">
    </div>

    <div>
        <img width="60" height="60" avatar="Donald Trump">
    </div>

    <div>
        <img width="60" height="60" avatar="Eva Kunis">
    </div>

    <div>
        <img width="60" height="60" avatar="Fritz John">
    </div>

    <div>
        <img width="60" height="60" avatar="George">
    </div>

    <div>
        <img width="60" height="60" avatar="Howard">
    </div>

    <div>
        <img width="60" height="60" avatar="Ingrid">
    </div>

    <div>
        <img width="60" height="60" avatar="John">
    </div>

    <div>
        <img width="60" height="60" avatar="Kira">
    </div>

    <div>
        <img width="60" height="60" avatar="Laura">
    </div>

    <div>
        <img width="60" height="60" avatar="Michael">
    </div>

    <div>
        <img width="60" height="60" avatar="Nora">
    </div>

    <div>
        <img width="60" height="60" avatar="Oscar">
    </div>

    <div>
        <img width="60" height="60" avatar="Peter">
    </div>

    <div>
        <img width="60" height="60" avatar="Quentin">
    </div>

    <div>
        <img width="60" height="60" avatar="Richard">
    </div>

    <div>
        <img width="60" height="60" avatar="Seinfeld">
    </div>

    <div>
        <img width="60" height="60" avatar="Tina">
    </div>

    <div>
        <img width="60" height="60" avatar="Ulf">
    </div>

    <div>
        <img width="60" height="60" avatar="Viktor">
    </div>

    <div>
        <img width="60" height="60" avatar="Wilfred">
    </div>

    <div>
        <img width="60" height="60" avatar="Xavier">
    </div>

    <div>
        <img width="60" height="60" avatar="Yanne">
    </div>

    <div>
        <img width="60" height="60" avatar="Zonk">
    </div>

    <div>
        <img width="60" height="60" avatar="">
    </div>

script.js

/*
     * LetterAvatar
     * 
     * Artur Heinze
     * Create Letter avatar based on Initials
     * based on https://gist.github.com/leecrossley/6027780
     */
    (function(w, d){


        function LetterAvatar (name, size) {

            name  = name || '';
            size  = size || 60;

            var colours = [
                    "#1abc9c", "#2ecc71", "#3498db", "#9b59b6", "#34495e", "#16a085", "#27ae60", "#2980b9", "#8e44ad", "#2c3e50", 
                    "#f1c40f", "#e67e22", "#e74c3c", "#ecf0f1", "#95a5a6", "#f39c12", "#d35400", "#c0392b", "#bdc3c7", "#7f8c8d"
                ],

                nameSplit = String(name).toUpperCase().split(' '),
                initials, charIndex, colourIndex, canvas, context, dataURI;


            if (nameSplit.length == 1) {
                initials = nameSplit[0] ? nameSplit[0].charAt(0):'?';
            } else {
                initials = nameSplit[0].charAt(0) + nameSplit[1].charAt(0);
            }

            if (w.devicePixelRatio) {
                size = (size * w.devicePixelRatio);
            }
                
            charIndex     = (initials == '?' ? 72 : initials.charCodeAt(0)) - 64;
            colourIndex   = charIndex % 20;
            canvas        = d.createElement('canvas');
            canvas.width  = size;
            canvas.height = size;
            context       = canvas.getContext("2d");
             
            context.fillStyle = colours[colourIndex - 1];
            context.fillRect (0, 0, canvas.width, canvas.height);
            context.font = Math.round(canvas.width/2)+"px Arial";
            context.textAlign = "center";
            context.fillStyle = "#FFF";
            context.fillText(initials, size / 2, size / 1.5);

            dataURI = canvas.toDataURL();
            canvas  = null;

            return dataURI;
        }

        LetterAvatar.transform = function() {

            Array.prototype.forEach.call(d.querySelectorAll('img[avatar]'), function(img, name) {
                name = img.getAttribute('avatar');
                img.src = LetterAvatar(name, img.getAttribute('width'));
                img.removeAttribute('avatar');
                img.setAttribute('alt', name);
            });
        };


        // AMD support
        if (typeof define === 'function' && define.amd) {
            
            define(function () { return LetterAvatar; });
        
        // CommonJS and Node.js module support.
        } else if (typeof exports !== 'undefined') {
            
            // Support Node.js specific `module.exports` (which can be a function)
            if (typeof module != 'undefined' && module.exports) {
                exports = module.exports = LetterAvatar;
            }

            // But always support CommonJS module 1.1.1 spec (`exports` cannot be a function)
            exports.LetterAvatar = LetterAvatar;

        } else {
            
            window.LetterAvatar = LetterAvatar;

            d.addEventListener('DOMContentLoaded', function(event) {
                LetterAvatar.transform();
            });
        }

    })(window, document);

style.css

body {
  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
}

pre {
  margin: 20px 0;
  padding: 20px;
  background: #fafafa;
}

.round { border-radius: 50%; }