Run results for: window.getComputedStyle vs. getBoundingClientRect

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 18_5 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.5 Mobile/15E148 Safari/604.1

Browser: Mobile Safari 18

Operating system: iOS 18.5

Device Platform: Mobile

Date tested: one year ago

getComputedStyle

2K/s

getBoundingClientRect

999/s

View exact numbers

Test name	Executions per second
✓ getComputedStyle	1,580 Ops/sec
getBoundingClientRect	999 Ops/sec

HTML Preparation code:

<div id="foo"></div>

Tests:

getComputedStyle
var i = 5000; while (i--) { checkDisplay('foo'); } function checkDisplay(id) { return window.getComputedStyle(document.getElementById(id), null).getPropertyValue("display") === "none"; }
getBoundingClientRect
var i = 5000; while (i--) { checkDisplay('foo'); } function checkDisplay(id) { return document.getElementById(id).getBoundingClientRect().width === 0; }