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document.hasFocus

The Document.hasFocus() method returns a Boolean value indicating whether the document or any element inside the document has focus. This method can be used to determine whether the active element in a document has focus.

When viewing a document, an element with focus is always the active element in the document, but an active element does not necessarily have focus. For example, an active element within a popup window that is not the foreground does not have focus.

Syntax

focused = document.hasFocus();

Return value

false if the active element in the document has no focus; true if the active element in the document has focus.

Example

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<title>TEST</title>
<style>
#message { font-weight: bold; }
</style>
<script>
setInterval( checkPageFocus, 200 );

function checkPageFocus() {
  var info = document.getElementById("message");

  if ( document.hasFocus() ) {
    info.innerHTML = "The document has the focus.";
  } else {
    info.innerHTML = "The document doesn't have the focus.";
  }
}

function openWindow() {
  window.open (
    "http://developer.mozilla.org/",
    "mozdev",
    "width=640,
    height=300,
    left=150,
    top=260"
  );
}
</script>
</head>
<body>
  <h1>JavaScript hasFocus example</h1>
  <div id="message">Waiting for user action</div>
  <div><button onclick="openWindow()">Open a new window</button></div>
</body>
</html>

Specification

Specification	Status	Comment
WHATWG HTML Living Standard The definition of 'Document.hasFocus()' in that specification.	Living Standard	Initial definition

Browser compatibility

Feature	Chrome	Edge	Firefox (Gecko)	Internet Explorer	Opera	Safari
Basic support	30	(Yes)	3.0 (1.9)	6.0	12.10	(Yes)