Run results for: replaceChild vs replaceChildren vs documentFragment

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 14_7_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.1.2 Mobile/15E148 Safari/604.1

Browser: Mobile Safari 14

Operating system: iOS 14.7.1

Device Platform: Mobile

Date tested: 3 years ago

Test name	Executions per second
replaceChild	830514.3 Ops/sec
replaceChildren	708921.9 Ops/sec
append documentFragment	402567.9 Ops/sec

HTML Preparation code:

<div id="container"></div>

Script Preparation code:

var elements = [document.createElement('div'), document.createElement('div')];
var fragment = document.createDocumentFragment();
var container = document.getElementById('container');

elements.forEach(element => fragment.appendChild(element));
container.appendChild(fragment);

Tests:

replaceChild
var changeIndex = 1; elements[changeIndex] = document.createElement('div'); container.replaceChild(elements[changeIndex], container.children[changeIndex]);
replaceChildren
var changeIndex = 1; elements[changeIndex] = document.createElement('div'); container.replaceChildren(elements)
append documentFragment
var changeIndex = 1; var newChildren = document.createDocumentFragment(); elements[changeIndex] = document.createElement('div'); elements.forEach(element => newChildren.appendChild(element)); while(container.firstChild) { container.firstChild.remove(); } container.appendChild(newChildren)

Run results for: replaceChild vs replaceChildren vs documentFragment

replaceChild

replaceChildren

append documentFragment