Run results for: resize event listener vs resizeObserver

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/110.0.0.0 YaBrowser/23.3.0.2246 Yowser/2.5 Safari/537.36

Browser: Yandex Browser 23

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
resizeObserver (body)	1823.6 Ops/sec
resizeObserver (container)	1838.1 Ops/sec
window resize event listener	1134.3 Ops/sec

HTML Preparation code:

<div class="container">
</div>

Tests:

resizeObserver (body)
this._resizeWatcher = new ResizeObserver(entry => { this._onResize(); }); this._resizeWatcher.observe(document.body); function _onResize() { document.querySelector('.container').style.setProperty('--viewport-width', window.innerWidth); } for (let i = 360; i <= 1920; i++) { window.resizeTo(i, 1000) }
resizeObserver (container)
this._resizeWatcher = new ResizeObserver(entry => { this._onResize(); }); this._resizeWatcher.observe(document.querySelector('.container')); function _onResize() { document.querySelector('.container').style.setProperty('--viewport-width', window.innerWidth); } for (let i = 360; i <= 1920; i++) { window.resizeTo(i, 1000) }
window resize event listener
document.querySelector('.container').style.setProperty('--viewport-width', window.innerWidth); window.addEventListener('resize', _onResize); function _onResize() { document.querySelector('.container').style.setProperty('--viewport-width', window.innerWidth); } for (let i = 360; i <= 1920; i++) { window.resizeTo(i, 1000) }

Run results for: resize event listener vs resizeObserver

resizeObserver (body)

resizeObserver (container)

window resize event listener