Run results for: querySelectorAll vs getElementsByClassName iteration

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.136 YaBrowser/20.2.3.320 (beta) Yowser/2.5 Safari/537.36

Browser: Yandex Browser 20

Operating system: Linux

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
querySelectorAll	380632.4 Ops/sec
getElementsByClassName	273318.1 Ops/sec

HTML Preparation code:

<div class="test"></div>
<div class="test"></div>
<div class="test"></div>
<div class="test"></div>
<div class="test"></div>
<div class="test"></div>
<div class="test"></div>
<div class="test"></div>
<div class="test"></div>
<div class="test"></div>

Tests:

querySelectorAll
const allTests = document.querySelectorAll('.test'); allTests.forEach(function (test) {});
getElementsByClassName
const allTests = document.getElementsByClassName('test'); const arrayAllTests = Array.from(allTests); arrayAllTests.forEach(function (test) {});