Run results for: childNodes vs children vs firstChild/nextSibling vs firstElementChild/nextElementSibling

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:94.0) Gecko/20100101 Firefox/94.0

Browser: Firefox 94

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
childNodes	2076801.2 Ops/sec
children	2384012.2 Ops/sec
firstChild nextSibling	4440420.5 Ops/sec
firstElementChild nextElementChild	14878308.0 Ops/sec
ChildNodes2	2194217.5 Ops/sec

HTML Preparation code:

<html>

<body>
    <div id='test'>
        <div name='a'></div>
        <div name='b'></div>
        <div name='c'></div>
    </div>
</body>

</html>

Script Preparation code:

var parent = document.getElementById('test');

Tests:

childNodes
parent.childNodes.forEach(function (node) { let n = node; });
children
for (let i = 0; i < parent.children.length; i++) { let n = parent.children[i]; }
firstChild nextSibling
let elem = parent.firstChild; do { let n = elem; } while (elem = elem.nextSibling)
firstElementChild nextElementChild
let elem = parent.firstElementChild; do { let n = elem; } while (elem = elem.nextElementSibling)
ChildNodes2
let children = parent.childNodes; for (let i = 0; i < children.length; i++) { let n = children[i]; }

Run results for: childNodes vs children vs firstChild/nextSibling vs firstElementChild/nextElementSibling

Fastest way to list children

childNodes

children

firstChild nextSibling

firstElementChild nextElementChild

ChildNodes2