Run results for: Creating elements with cloneNode (template vs. normal element)

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.3 Safari/605.1.15

Browser: Safari 18

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Simple - JavaScript

3.5M/s

Simple - Template

2.5M/s

Complex - JavaScript

1.0M/s

Complex - Template

681K/s

View exact numbers

Test name	Executions per second
✓ Simple - JavaScript	3,469,652 Ops/sec
Simple - Template	2,506,702 Ops/sec
Complex - JavaScript	1,005,319 Ops/sec
Complex - Template	680,804 Ops/sec

Script Preparation code:

var simpleTemplate = document.createElement("template");
simpleTemplate.innerHTML = `<span class="simple"></span>`;
  
var complexTemplate = document.createElement("template");
complexTemplate.innerHTML =
  `<span class="complex">
     <span class="simple-1"></span>
     <span class="simple-2">
       <span class="simple-2-1"></span>
     </span>
     <span class="simple-3">
       <span class="simple-3-1"></span>
     </span>
     <span class="simple-4"></span>
   </span>`;

var simpleElement = document.createElement("span");
simpleElement.classList.add("simple");
  
var complexElement = document.createElement("span");
complexElement.classList.add("complex");
complexElement.innerHTML =
  `<span class="simple-1"></span>
   <span class="simple-2">
     <span class="simple-2-1"></span>
   </span>
   <span class="simple-3">
     <span class="simple-3-1"></span>
   </span>
   <span class="simple-4"></span>`;

Tests:

Simple - Template
let el = document.createElement("div"); let content = simpleTemplate.content.cloneNode(true); el.appendChild(content);
Simple - JavaScript
let el = document.createElement("div"); let content = simpleElement.cloneNode(true); el.appendChild(content);
Complex - Template
let el = document.createElement("div"); let content = complexTemplate.content.cloneNode(true); el.appendChild(content);
Complex - JavaScript
let el = document.createElement("div"); let content = complexElement.cloneNode(true); el.appendChild(content);