Benchmark: getBoundingClientRect vs offset

HTML Preparation code:

<div id="el" style="transform: rotateZ(45deg)">
  <h2>Lorem ipsum dolor sit amet</h2>
</div>

Script Preparation code:

function getLocalDOMRect(el) {
  let offsetTop = 0;
  let offsetLeft = 0;
  const width = el.offsetWidth;
  const height = el.offsetHeight;
  while (el instanceof HTMLElement) {
    offsetTop += el.offsetTop;
    offsetLeft += el.offsetLeft;
    el = el.offsetParent;
  }

  return new DOMRect(offsetLeft, offsetTop, width, height);
}

const el = document.getElementById("el");

Tests:

getBoundingClientRect
const { left, right, top, bottom } = el.getBoundingClientRect();
getLocalDOMRect
const { left, right, top, bottom } = getLocalDOMRect(el);
Access offset properties directly
const { offsetWidth, offsetHeight, offsetTop } = el;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
getBoundingClientRect
getLocalDOMRect
Access offset properties directly

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 3 days ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36

Browser/OS: Chrome 122 on Linux

View result in a separate tab

Test name	Executions per second
getBoundingClientRect	356027.9 Ops/sec
getLocalDOMRect	63424.5 Ops/sec
Access offset properties directly	198019.7 Ops/sec

getBoundingClientRect vs offset (version: 0)

Comparing performance of: getBoundingClientRect vs getLocalDOMRect vs Access offset properties directly

Created: one year ago by: Guest

Jump to the latest result

getBoundingClientRect

getLocalDOMRect

Access offset properties directly

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A