Run results for: offsetWidth / offsetHeight vs. getBoundingClientRect()

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 18_3_2 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.3.1 Mobile/15E148 Safari/604.1

Browser: Mobile Safari 18

Operating system: iOS 18.3.2

Device Platform: Mobile

Date tested: one year ago

offsetWidth / offsetHeight (destructured)

11.1M/s

offsetWidth / offsetHeight (destructured and renamed)

9.6M/s

offsetWidth / offsetHeight (simple property access)

6.2M/s

getBoundingClientRect() (simple property access)

2.8M/s

getBoundingClientRect() (destructured)

2.8M/s

View exact numbers

Test name	Executions per second
✓ offsetWidth / offsetHeight (destructured)	11,079,985 Ops/sec
offsetWidth / offsetHeight (destructured and renamed)	9,564,654 Ops/sec
offsetWidth / offsetHeight (simple property access)	6,155,272 Ops/sec
getBoundingClientRect() (simple property access)	2,827,365 Ops/sec
getBoundingClientRect() (destructured)	2,825,459 Ops/sec

HTML Preparation code:

<div id="el">
  <h2>Lorem ipsum dolor sit amet</h2>
</div>

Script Preparation code:

var el = document.getElementById("el");

Tests:

offsetWidth / offsetHeight (destructured and renamed)
const { offsetWidth: width, offsetHeight: height } = el; const perim = (width + height) * 2;
offsetWidth / offsetHeight (destructured)
const { offsetWidth, offsetHeight } = el; const perim = (offsetWidth + offsetHeight) * 2;
offsetWidth / offsetHeight (simple property access)
const width = el.offsetWidth; const height = el.offsetHeight; const perim = (width + height) * 2;
getBoundingClientRect() (destructured)
const { width, height } = el.getBoundingClientRect(); const perim = (width + height) * 2;
getBoundingClientRect() (simple property access)
const rect = el.getBoundingClientRect(); const width = rect.width; const height = rect.height; const perim = (width + height) * 2;