Benchmark: getElementById vs getElementsByClassName

HTML Preparation code:

<div id="header">
		<div id="logo">
			<img src="images/logo.png" alt="the network"/>
		</div>	
		<div id="search">
			<form method="get">
				<input type="text" name="post" placeholder="thoughts?"/>
				<input type="submit" value="Post">
			</form>
		</div>
	</div>
</div>

Tests:

getElementById.childNodes
var form = document.getElementById("search").childNodes[0];
getElementById.getElementsByTagName
var form = document.getElementById("search").getElementsByTagName("form")[0];
getElementsByTagName
var form = document.getElementsByTagName("form")[0];

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
getElementById.childNodes
getElementById.getElementsByTagName
getElementsByTagName

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 9 months ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser/OS: Chrome 114 on Linux

View result in a separate tab

Test name	Executions per second
getElementById.childNodes	3884622.0 Ops/sec
getElementById.getElementsByTagName	2888361.0 Ops/sec
getElementsByTagName	3415455.0 Ops/sec

getElementById vs getElementsByClassName (version: 0)

getElementById vs getElementsByClassName

Comparing performance of: getElementById.childNodes vs getElementById.getElementsByTagName vs getElementsByTagName

Created: 4 years ago by: Guest

Jump to the latest result

getElementById.childNodes

getElementById.getElementsByTagName

getElementsByTagName

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A