Run results for: Cached querySelector

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 18_3_2 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) GSA/362.0.741018905 Mobile/15E148 Safari/604.1

Browser: Mobile Safari 18

Operating system: iOS 18.3.2

Device Platform: Mobile

Date tested: one year ago

Test name	Executions per second
uncached	17906956.0 Ops/sec
cached	544288512.0 Ops/sec

HTML Preparation code:

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

Script Preparation code:

var cache = {};

Tests:

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

Run results for: Cached querySelector

Testing if caching querySelector makes a diference

uncached

cached