Benchmark: getElementById + getElementByClassName vs querySelector

HTML Preparation code:

<div id="testElement">
  <div class="testElementChild1">1</div>
  <div class="testElementChild2">2</div>
  <div class="testElementChild3">3</div>
  <div class="testElementChild4">4</div>
  <div class="testElementChild5">5</div>
</div>

Script Preparation code:

var doc = document;
var testElement = doc.getElementById('testElement');

Tests:

getElementsById + getElementsByClassName
var test = doc.getElementById('testElement').getElementsByClassName('testElementChild3').innerHTML;
querySelector + querySelector
var test = doc.querySelector('#testElement').querySelector('.testElementChild3').innerHTML;
querySelector
var test = doc.querySelector('#testElement .testElementChild3').innerHTML;
cache + getElementsByClassName
var test = testElement.getElementsByClassName('testElementChild3').innerHTML;
cache + querySelector
var test = testElement.querySelector('.testElementChild3').innerHTML;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
getElementsById + getElementsByClassName
querySelector + querySelector
querySelector
cache + getElementsByClassName
cache + querySelector

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/102.0.0.0 Safari/537.36

Browser/OS: Chrome 102 on Windows

View result in a separate tab

Test name	Executions per second
getElementsById + getElementsByClassName	2167443.0 Ops/sec
querySelector + querySelector	1372145.0 Ops/sec
querySelector	1909225.0 Ops/sec
cache + getElementsByClassName	2477966.0 Ops/sec
cache + querySelector	2492925.0 Ops/sec

getElementById + getElementByClassName vs querySelector (version: 0)

getElementById + getElementByClass vs querySelector

Comparing performance of: getElementsById + getElementsByClassName vs querySelector + querySelector vs querySelector vs cache + getElementsByClassName vs cache + querySelector

Created: 3 years ago by: Guest

Jump to the latest result

getElementsById + getElementsByClassName

querySelector + querySelector

querySelector

cache + getElementsByClassName

cache + querySelector

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A