Run results for: getElementById vs querySelector (class vs id)

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:139.0) Gecko/20100101 Firefox/139.0

Browser: Firefox 139

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

getElementById

6.0M/s

querySelector

4.1M/s

View exact numbers

Test name	Executions per second
✓ getElementById	6,032,731 Ops/sec
querySelector	4,146,009 Ops/sec

HTML Preparation code:

<div id="t" class="t"></div>

Tests:

getElementById
var el = document.getElementById('t'); var className = el.className;
querySelector
var el = document.querySelector('.t'); var className = el.className;