Run results for: getElementsByClass vs. querySelector

Run details:

User agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.87 Safari/537.36

Browser: Chrome 67

Operating system: Windows 7

Device Platform: Desktop

Date tested: 5 years ago

Test name	Executions per second
queryselector	2512175.2 Ops/sec
class by name	2661412.8 Ops/sec

HTML Preparation code:

<div class="wrapper">
  <div class="item"></div>
    <div class="item"></div>
    <div class="item"></div>
    <div class="item"></div>
</div>
<script src='https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js'></script>

Tests:

queryselector
document.querySelector(".item");
class by name
document.getElementsByClassName("test");

Run results for: getElementsByClass vs. querySelector

queryselector

class by name