JSFiddle - React, Tailwind, and code Playground

HTML

<code id="seeTime"></code>

JavaScript

(function() {

    var 
        myconsole = function(ref) { 
            
            var times = [], xwrite = $("#seeTime");
            
            this.time = function(data) {
                times[data] = (new Date()).getTime();
            }
            
            this.timeEnd = function(data) {
                xwrite.append("<span><b>"+data+":</b> "+((new Date()).getTime() - times[data])+"ms</span><br />");
            }
            
            return this;
                                        
       }.call({});
    
    var 
        loops = 1e6,
        foo, 
        undefined;
             
    myconsole.time('typeof');
    while(loops--) {
        if( typeof foo !== 'undefined' ) {}
    }
    myconsole.timeEnd('typeof');
             
    loops = 1e6;
    
    myconsole.time('undefined');
    while(loops--) {
        if( foo !== undefined) {}
    }
    myconsole.timeEnd('undefined');
    
    loops = 1e6;
    
            
    myconsole.time('void 0');
    while(loops--) {
        if( foo !== void 0) {}
    }
    myconsole.timeEnd('void 0');

    
}());