Run results for: Cached querySelector single

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:124.0) Gecko/20100101 Firefox/124.0

Browser: Firefox 124

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

Benchmark engine: Benchmark.js

cached

2.6M/s

uncached

2.6M/s

View exact numbers

Test name	Executions per second
✓ cached	2,595,682 Ops/sec
uncached	2,589,621 Ops/sec

HTML Preparation code:

<div id="fir" class="hi">
  <div id='no' class="ss">
  	<div id='ff' class="fox">
      <button class="target"></button>
    </div>
  </div>
</div>

Script Preparation code:

var cache = {};

Tests:

uncached
var el = document.querySelector('target');
cached
var el = cache['target']; if (!el) { el = document.querySelector('target'); cache['target'] = el; }

Run results for: Cached querySelector single

Testing if caching querySelector makes a diference

uncached

cached