Run results for: getElementsByClassName()[0] vs querySelectorAll

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:79.0) Gecko/20100101 Firefox/79.0

Browser: Firefox 79

Operating system: Windows

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
By Class Name	2227547.5 Ops/sec
Query Selector	2271242.8 Ops/sec

HTML Preparation code:

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

Tests: