Run results for: 6 properties - style.setProperty vs style.cssText vs style vs Object.assign vs setAttribute vs classList

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: 5 months ago

Test name	Executions per second
style.setProperty	408.5 Ops/sec
style.cssText	102.4 Ops/sec
style	92.9 Ops/sec
Object.assign	89.1 Ops/sec
setAttribute	1036.7 Ops/sec
classList	806.8 Ops/sec

HTML Preparation code:

<style>
  :root {
  	--test-color: 'red';
  }
  
  .test {
  	color: var(--test-color);
  }
  
  .test-blue {
  	--test-color: 'blue';
  }
  
</style>

<div id="test"></div>

​x
 
<style>
  :root {
    --test-color: 'red';
  }
  
  .test {
    color: var(--test-color);
  }
  
  .test-blue {
    --test-color: 'blue';
  }
  
</style>
​
<div id="test"></div>

Script Preparation code:

el = document.getElementById("test");

 
el = document.getElementById("test");

Tests:

style.setProperty
let i = 0; while (i < 10000) { el.style.setProperty("--test-color","blue"); i++; }
let i = 0;

while (i < 10000) {
el.style.setProperty("--test-color","blue");
i++;
}
style.cssText
let i = 0; while (i < 10000) { el.style.cssText = "color:red;border:1vmin solid red;padding:0.5vmin;background-color:black;height:1vh;width:1vw;"; i++; }
let i = 0;

while (i < 10000) {
el.style.cssText = "color:red;border:1vmin solid red;padding:0.5vmin;background-color:black;height:1vh;width:1vw;";
i++;
}

style

let i = 0;

while (i < 10000) {
  el.style = "color:red;border:1vmin solid red;padding:0.5vmin;background-color:black;height:1vh;width:1vw;";
  i++;
}

 
let i = 0;​while (i < 10000) {  el.style = "color:red;border:1vmin solid red;padding:0.5vmin;background-color:black;height:1vh;width:1vw;";  i++;}

Object.assign

let style = {
  height: '1vh',
  width: '1vw',
  color: 'red',
  border: '1vmin solid red',
  backgroundColor: 'black',
  padding: '0.5vmin'
};
let i = 0;

while (i < 10000) {
  Object.assign(el.style, style);
  i++;
}

 
let style = {  height: '1vh',  width: '1vw',  color: 'red',  border: '1vmin solid red',  backgroundColor: 'black',  padding: '0.5vmin'};let i = 0;​while (i < 10000) {  Object.assign(el.style, style);  i++;}

setAttribute
let i = 0; while (i < 10000) { el.setAttribute('style',"color:red;border:1vmin solid red;padding:0.5vmin;background-color:black;height:1vh;width:1vw;"); i++; }
let i = 0;

while (i < 10000) {
el.setAttribute('style',"color:red;border:1vmin solid red;padding:0.5vmin;background-color:black;height:1vh;width:1vw;");
i++;
}
classList
let i = 0; while (i < 10000) { el.classList.add('test-blue'); i++; }
let i = 0;

while (i < 10000) {
el.classList.add('test-blue');
i++;
}