Run results for: Realistic: querySelector vs querySelectorAll vs getElementsByClassName vs querySelector (ID) vs getElementsByID

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.36

Browser: Chrome 135

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

getElementsByID

38.5M/s

getElementsByClassName

33.1M/s

querySelector

24.4M/s

querySelector (ID)

11.2M/s

querySelectorAll

4.7M/s

View exact numbers

Test name	Executions per second
✓ getElementsByID	38,498,800 Ops/sec
getElementsByClassName	33,065,460 Ops/sec
querySelector	24,389,630 Ops/sec
querySelector (ID)	11,245,623 Ops/sec
querySelectorAll	4,691,844 Ops/sec

HTML Preparation code:

<div class="test" id="test"></div>
<div class="test"></div>
<div class="test"></div>
<div class="test"></div>
<div class="test"></div>
<div class="blash">
  <div class="sds">
    <div class="test"></div>
  </div>
</div>
<div class="test"></div>
<div class="blash">
  <div class="sds">
    <div class="test"></div>
  </div>
</div>
<div class="test"></div>
<div class="test"></div>
<div class="blash">
  <div class="sds">
    <div class="test"></div>
  </div>
</div>
<div class="test"></div>
<div class="test"></div>
<div class="test"></div>
<div class="test"></div>

Tests:

querySelector
document.querySelector(".test")
querySelectorAll
document.querySelectorAll(".test")
getElementsByClassName
document.getElementsByClassName("test")
querySelector (ID)
document.querySelector("#test")
getElementsByID
document.getElementById("test")