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The clientX read-only property of the MouseEvent interface provides the horizontal coordinate within the application's client area at which the event occurred (as opposed to the coordinates within the page). For example, clicking in the top-left corner of the client area will always result in a mouse event with a clientX value of 0, regardless of whether the page is scrolled horizontally. Originally, this property was defined as a long integer. The CSSOM View Module redefined it as a double float. See the Browser compatibility section for details.

Syntax

var x = instanceOfMouseEvent.clientX

Return value

A number

Example

<!DOCTYPE html> 
<html>
  <head>
    <title>clientX/clientY example</title>

    <script>
      function showCoords(evt){
        alert(
          "clientX value: " + evt.clientX + "\n" +
          "clientY value: " + evt.clientY + "\n"
        );
      }
    </script>
  </head>
  <body onmousedown="showCoords(event)">
    <p>To display the mouse coordinates click anywhere on the page.</p>
  </body>
</html>

Specifications

Specification Status Comment
CSS Object Model (CSSOM) View Module
The definition of 'clientX' in that specification.
Working Draft Redefines MouseEvent from long to double
Document Object Model (DOM) Level 3 Events Specification
The definition of 'MouseEvent.clientX' in that specification.
Working Draft No change from Document Object Model (DOM) Level 2 Events Specification.
Document Object Model (DOM) Level 2 Events Specification
The definition of 'MouseEvent.clientX' in that specification.
Recommendation Initial definition.

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support (Yes) (Yes) (Yes) 6 (Yes) (Yes)
Redefined from long to double 56 ? ? ? ? ?
Feature Android Webview Chrome for Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support (Yes) (Yes) (Yes) ? ? ? ?
Redefined from long to double 56 56 ? ? ? ? ?

See also

Document Tags and Contributors

 Last updated by: vp2177,