Run results for: classList.contains() vs closest() performance

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 18_3_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.3 Mobile/15E148 Safari/604.1

Browser: Mobile Safari 18

Operating system: iOS 18.3.1

Device Platform: Mobile

Date tested: 10 months ago

contains

88.4M/s

closest

6.2M/s

View exact numbers

Test name	Executions per second
✓ contains	88,409,168 Ops/sec
closest	6,160,420 Ops/sec

HTML Preparation code:

<div class='div1'>
  <div class='div2'>
    <div class='div3'>
    </div>
  </div>
</div>

Script Preparation code:

var box = document.querySelector('.div1')
var clicked = document.querySelector('.div3')

Tests: