Web/API/MouseEvent/movementX

The movementX read-only property of the MouseEvent interface provides the difference in the X coordinate of the mouse pointer between the given event and the previous mousemove event. In other words, the value of the property is computed like this: currentEvent.movementX = currentEvent.screenX - previousEvent.screenX.

Syntax

var xShift = instanceOfMouseEvent.movementX;

Return value

A number

Example

This example logs the amount of mouse movement using movementX and movementY.

HTML

<p id="log">Move your mouse around.</p>

JavaScript

function logMovement(event) {
  log.insertAdjacentHTML('afterbegin', `movement: ${event.movementX}, ${event.movementY}<br>`);
  while (log.childNodes.length > 128) log.lastChild.remove()
}

const log = document.getElementById('log');
document.addEventListener('mousemove', logMovement);

Result

Specifications

Specification	Status	Comment
Pointer LockThe definition of 'MouseEvent.movementX' in that specification.	Candidate Recommendation	Initial definition

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`movementX`	Chrome Full support 37 Full support 37 No support 22 — 37 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Edge Full support 13	Firefox Full support 41 Full support 41 No support 1 — 41 Prefixed' Prefixed' Implemented with the vendor prefix: moz	IE No support No	Opera Full support Yes	Safari Full support 9 Full support 9 No support 6 — 8 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	WebView Android Full support 37 Full support 37 No support ? — 37 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Chrome Android Full support 37 Full support 37 No support ? — 37 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Firefox Android Full support 41 Full support 41 No support 4 — 41 Prefixed' Prefixed' Implemented with the vendor prefix: moz	Opera Android Full support Yes	Safari iOS Full support 8 Full support 8 No support 6 — 8 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Samsung Internet Android Full support 3.0 Full support 3.0 No support ? — 3.0 Prefixed' Prefixed' Implemented with the vendor prefix: webkit

Legend

Full support: Full support
No support: No support
Requires a vendor prefix or different name for use.': Requires a vendor prefix or different name for use.