focusOffset property

Retrieves the end position of a selection that is relative to the focusNode / extentNode.

HTML5 A vocabulary and associated APIs for HTML and XHTML, Section 7.6.1Internet Explorer 9




p = object.focusOffset


Property values

Type: Integer

The end position of the selection.

Standards information


The Selection.extentOffset alias for this property is only available in Microsoft Edge.

focusOffset typically refers to a character position within the text portion of the focusNode.


The following example uses focusOffset to show the offset value for the end of a selection when you release the mouse button.

<!DOCTYPE html>
<!-- this example displays the character offset from anchor node of your selection-->
    <title>Focus Offset Example</title>        
    <script type="text/javascript">         
      function getfocusOffset() {
        if (window.getSelection) {                      //only works if supported
           var selection = window.getSelection ();      //get the selection object     
           var focusOffsetProp = selection.focusOffset;   //get the offset
           alert ( "Offset: \n" + focusOffsetProp.toString());                                 
<div onmouseup="getfocusOffset()">    <!-- call the function when the mouse button is released -->
        Use the mouse to select some text within this field.
        When <strong>the left <em>button</em> is released</strong>, a dialog box appears with the anchor offset.
        The nested tags <strong>here and <em>there</em> can</strong> demonstrate different offsets as well.

See also

focusNode (extentNode)
anchorNode (baseNode)
anchorOffset (baseOffset)