Run results for: 1 css var - style.setProperty vs style.cssText vs style vs Object.assign vs setAttribute

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36

Browser: Chrome 131

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Object.assign

418/s

setAttribute

358/s

style.cssText

170/s

style

141/s

style.setProperty

130/s

View exact numbers

HTML Preparation code:

<div id="test"><div style="height: calc(var(--w, 1) * 1px); background-color:red;"></div></div>

Script Preparation code:

el = document.getElementById("test");
rn = ()=>Math.floor(10+Math.random(5));

Tests:

style.setProperty
let i = 0; while (i < 10000) { el.style.setProperty("--w", rn); i++; }
style.cssText
let i = 0; while (i < 10000) { el.style.cssText = `--w: ${rn()};`; i++; }
style
let i = 0; while (i < 10000) { el.style = `--w: ${rn()};`; i++; }
Object.assign
let i = 0; while (i < 10000) { Object.assign(el.style, { ['--w']: rn(), }); i++; }
setAttribute
let i = 0; while (i < 10000) { el.setAttribute('style',`--w: ${rn()};`); i++; }