Run results for: DataAttribute vs Class Selector vs ID Selector (multi-class)

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.130 Safari/537.36

Browser: Chrome 79

Operating system: Windows

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
Class	3368450.2 Ops/sec
ID	2465419.8 Ops/sec
data attribute	2109560.5 Ops/sec

HTML Preparation code:

<div class="hello" id="hello" data-hello>Hello</div>	
<div class="hello class2" id="hello2" data-hello data-hello2>Hello</div>	
<div class="hello class3" id="hello3" data-hello data-hello3>Hello</div>	
<div class="hello class4" id="hello4" data-hello data-hello4>Hello</div>	
<div class="hello class5" id="hello5" data-hello data-hello5>Hello</div>	
<div class="hello class6" id="hello6" data-hello data-hello6>Hello</div>	
<div class="hello class7" id="hello7" data-hello data-hello7>Hello</div>	
<div class="hello class8" id="hello8" data-hello data-hello8>Hello</div>	
<div class="hello class9" id="hello9" data-hello data-hello9>Hello</div>
<div class="hello class10" id="hello10" data-hello data-hello10>Hello</div>		
<div class="hello class11" id="hello11" data-hello data-hello11>Hello</div>	
<div class="hello class12" id="hello12" data-hello data-hello12>Hello</div>	
<div class="hello class13" id="hello13" data-hello data-hello13>Hello</div>	
<div class="hello class14" id="hello14" data-hello data-hello14>Hello</div>	
<div class="hello class15" id="hello15" data-hello data-hello15>Hello</div>

Tests:

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

Run results for: DataAttribute vs Class Selector vs ID Selector (multi-class)

Class

ID

data attribute