Run results for: CssText vs Styling vs classList add

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36

Browser: Chrome 125

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

classList add

1.6M/s

styling

735K/s

csstext

225K/s

View exact numbers

Test name	Executions per second
✓ classList add	1,583,211 Ops/sec
styling	735,450 Ops/sec
csstext	225,369 Ops/sec

HTML Preparation code:

<div id="myid">hi</div>
<style>
    .wide {
      width: 100px;
    }
    .long {
      left: 100px;
      height: 100px;
    }
    .blue {
      top: 100px;
    }
</style>

Script Preparation code:

var a = document.getElementById("myid");
a.style.position = "absolute";

Tests:

csstext
a.style.cssText += "left: 100px ;top: 100px; width: 100px; height: 100px";
styling
a.style.left = "100px" a.style.top = "100px" a.style.width = "100px" a.style.height = "100px"
classList add
a.classList.add('wide','long','blue')