Run results for: getElementById vs querySelectorAll

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.138 Safari/537.36

Browser: Chrome 81

Operating system: Mac OS X 10.15.4

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
getElementById	4051480.8 Ops/sec
querySelectorAll	1089148.4 Ops/sec

HTML Preparation code:

<div id="testElement" class="test" data-test="1"></div>

AخA
 
<div id="testElement" class="test" data-test="1"></div>

Tests:

getElementById
var el = document.getElementById('testElement'); var className = el.className;
var el = document.getElementById('testElement');
var className = el.className;
querySelectorAll
var el = document.querySelectorAll('[data-a="1"]'); var className = el.className;
var el = document.querySelectorAll('[data-a="1"]');
var className = el.className;