HTML Code

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <title>getElementsByClassName multiple</title>
  <style>.red { background: #fecaca; } .test { border: 2px solid #333; padding: 8px; margin: 8px; }</style>
</head>
<body>
  <div id="box">
    <div class="red">Red only</div>
    <div class="test">Test only</div>
    <div class="red test">Both classes</div>
  </div>
  <pre id="out"></pre>
  <script>
    var matches = document.getElementById("box").getElementsByClassName("red test");
    document.getElementById("out").textContent = matches.length + "\n" + matches[0].textContent;
  </script>
</body>
</html>

Lines: 0 | Characters: 0

Live Preview Auto-refresh on Run

Element.getElementsByClassName — multiple classes (Try It)