Editing innerHTML vs createElement() and appendChild() This edit will create a new revision. Your details (optional) Name Email (won’t be displayed; might be used for Gravatar) URL Test case details Title * Published (uncheck if you want to fiddle around before making the page public) Description (in case you feel further explanation is needed)(Markdown syntax is allowed) Compares the performance of adding elements to DOM by using strings and innerHTML and creating DOMElement objects and appending them with appendChild(). Are you a spammer? (just answer the question) Preparation code Preparation code HTML (this will be inserted in the <body> of a valid HTML5 document in standards mode) (useful when testing DOM operations or including libraries) <script> /* * DOMParser HTML extension * 2012-02-02 * * By Eli Grey, http://eligrey.com * Public domain. * NO WARRANTY EXPRESSED OR IMPLIED. USE AT YOUR OWN RISK. */ /*! @source https://gist.github.com/1129031 */ /*global document, DOMParser*/ (function(DOMParser) { "use strict"; var DOMParser_proto = DOMParser.prototype , real_parseFromString = DOMParser_proto.parseFromString ; // Firefox/Opera/IE throw errors on unsupported types try { // WebKit returns null on unsupported types if ((new DOMParser).parseFromString("", "text/html")) { // text/html parsing is natively supported return; } } catch (ex) {} DOMParser_proto.parseFromString = function(markup, type) { if (/^\s*text\/html\s*(?:;|$)/i.test(type)) { var doc = document.implementation.createHTMLDocument("") , doc_elt = doc.documentElement , first_elt ; doc_elt.innerHTML = markup; first_elt = doc_elt.firstElementChild; if ( // are we dealing with an entire document or a fragment? doc_elt.childElementCount === 1 && first_elt.localName.toLowerCase() === "html" ) { doc.replaceChild(first_elt, doc_elt); } return doc; } else { return real_parseFromString.apply(this, arguments); } }; }(DOMParser)); </script> Include JavaScript libraries as follows: <script src="//cdn.ext/library.js"></script> Define setup for all tests (variables, functions, arrays or other objects that will be used in the tests) (runs before each clocked test loop, outside of the timed code region) (e.g. define local test variables, reset global variables, clear canvas, etc.) (see FAQ) Define teardown for all tests (runs after each clocked test loop, outside of the timed code region) (see FAQ) Code snippets to compare Test 1 Title Async (check if this is an asynchronous test) Code document.body.innerHTML += '<div class="test"><p>This is a test</p></div>'; Test 2 Title Async (check if this is an asynchronous test) Code var div = document.createElement('div'); div.className = 'test'; var p = document.createElement('p'); p.innerText = 'This is a test'; div.appendChild(p); document.body.appendChild(div); Test 3 Title Async (check if this is an asynchronous test) Code var parser = new DOMParser(); var doc = parser.parseFromString('<div class="test"><p>This is a test</p></div>', 'text/html'); document.body.appendChild(doc.body.childNodes[0]);