Run results for: innerHTML vs insertAdjacentHTML vs appendChild vs append vs insertAdjacentElement

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 16_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) GSA/271.3.546369769 Mobile/15E148 Safari/604.1

Browser: Mobile Safari 16

Operating system: iOS 16.1

Device Platform: Mobile

Date tested: one year ago

Test name	Executions per second
innerHTML	97868.9 Ops/sec
insertAdjacentHTML	97044.3 Ops/sec
appendChild	88260.5 Ops/sec
append	75719.4 Ops/sec
insertAdjacentElement	83547.2 Ops/sec

Script Preparation code:

// Change this number to see how well they scale
repeat = 10;

Tests:

innerHTML
const box = document.createElement('div'); let html = ''; for (let i = 0; i < repeat; i++) html += '<div class="a b"><div>Test</div></div>'; box.innerHTML += html;
insertAdjacentHTML
const box = document.createElement('div'); let html = ''; for (let i = 0; i < repeat; i++) html += '<div class="a b"><div>Test</div></div>'; box.insertAdjacentHTML('beforeend', html);
appendChild
const box = document.createElement('div'); const els = []; for (let i = 0; i < repeat; i++) { const div2 = document.createElement('div'); div2.innerText = 'Test'; const div1 = document.createElement('div'); div1.className = 'a b'; div1.appendChild(div2); els.push(div1); } els.forEach(el => box.appendChild(el));
append
const box = document.createElement('div'); const els = []; for (let i = 0; i < repeat; i++) { const div2 = document.createElement('div'); div2.innerText = 'Test'; const div1 = document.createElement('div'); div1.className = 'a b'; div1.append(div2); els.push(div1); } box.append(...els);
insertAdjacentElement
const box = document.createElement('div'); const els = []; for (let i = 0; i < repeat; i++) { const div2 = document.createElement('div'); div2.innerText = 'Test'; const div1 = document.createElement('div'); div1.className = 'a b'; div1.insertAdjacentElement('beforeend', div2); els.push(div1); } els.forEach(el => box.insertAdjacentElement('beforeend', el));