JSFiddle - React, Tailwind, and code Playground

by pseudosavant

HTML

<div id="fori">for (i=0...): <span></span></div>
<div id="forin">for (i in ...): <span></span></div>

JavaScript

var test = 0, fori = 0, forin = 0, a = [], start = 0, end = 0, i, l;

for (i=0; i<100000; i++) { // Test data
    a.push(Math.random());
}

start = +new Date();
for (i=0, l=a.length; i<l; i++) {
    test++;
}
fori = +new Date() - start;

start = +new Date();
for (i in a) {
    test++;
}
forin = +new Date() - start;

if (console && console.log) console.log(test);

$("#fori span").html(fori);
$("#forin span").html(forin);