Run results for: DataAttribute vs Class Selector vs ID Selector

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 18_1_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.1.1 Mobile/15E148 Safari/604.1

Browser: Mobile Safari 18

Operating system: iOS 18.1.1

Device Platform: Mobile

Date tested: one year ago

8.6M/s

data attribute

7.9M/s

Class

7.0M/s

View exact numbers

Test name	Executions per second
✓ ID	8,561,230 Ops/sec
data attribute	7,931,740 Ops/sec
Class	6,984,072 Ops/sec

HTML Preparation code:

<div class="hello" id="hello" data-hello>Hello</div>

Tests:

Class
document.querySelector('.hello');
ID
document.querySelector('#hello');
data attribute
document.querySelector('[data-hello]');