Run results for: resize event listener vs resize observer

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/130.0.0.0 Safari/537.36

Browser: Chrome 130

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 7 days ago

Test name	Executions per second
resizeObserver (body)	12785.3 Ops/sec
window resize event listener	5678.5 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() { console.log('resized') } for (let i = 360; i <= 1920; i++) { window.resizeTo(i, 1000) }
window resize event listener
window.addEventListener('resize', _onResize); function _onResize() { console.log('resize') } for (let i = 360; i <= 1920; i++) { window.resizeTo(i, 1000) }