Web/API/WheelEvent

The WheelEvent interface represents events that occur due to the user moving a mouse wheel or similar input device.

Important: This is the standard wheel event interface to use. Old versions of browsers implemented the non-standard and non-cross-browser-compatible MouseWheelEvent and MouseScrollEvent interfaces. Use this interface and avoid the non-standard ones.

Do not confuse the wheel event with the scroll event: The default action of a wheel event is implementation-defined. Thus, a wheel event doesn't necessarily dispatch a scroll event. Even when it does, that doesn't mean that the delta* values in the wheel event necessarily reflect the content's scrolling direction. Therefore, do not rely on delta* properties to get the content's scrolling direction. Instead, detect value changes to scrollLeft and scrollTop of the target in the scroll event.

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Constructor

WheelEvent()

Creates a WheelEvent object.

Properties

This interface inherits properties from its ancestors, MouseEvent, UIEvent, and Event.

WheelEvent.deltaXRead only

Returns a double representing the horizontal scroll amount.

WheelEvent.deltaYRead only

Returns a double representing the vertical scroll amount.

WheelEvent.deltaZRead only

Returns a double representing the scroll amount for the z-axis.

WheelEvent.deltaModeRead only

Returns an unsigned long representing the unit of the delta* values' scroll amount. Permitted values are:

Constant	Value	Description
WheelEvent.DOM_DELTA_PIXEL	0x00	The delta* values are specified in pixels.
WheelEvent.DOM_DELTA_LINE	0x01	The delta* values are specified in lines.
WheelEvent.DOM_DELTA_PAGE	0x02	The delta* values are specified in pages.

Methods

This interface doesn't define any specific methods, but inherits methods from its ancestors, MouseEvent, UIEvent, and Event.

Specifications

Specification	Status	Comment
UI EventsThe definition of 'The WheelEvent interface' in that specification.	Working Draft
Document Object Model (DOM) Level 3 Events SpecificationThe definition of 'WheelEvent' in that specification.	Obsolete	Initial definition.

Browser compatibility

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

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
WheelEvent	Chrome Full support 31	Edge Full support 12	Firefox Full support 17	IE Full support 9	Opera Full support 18	Safari Full support 6.1	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 17	Opera Android Full support Yes	Safari iOS No support No	Samsung Internet Android Full support Yes
WheelEvent() constructor	Chrome Full support Yes	Edge Full support ≤18	Firefox Full support 17	IE No support No	Opera Full support Yes	Safari Full support 6.1	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 17	Opera Android Full support Yes	Safari iOS No support No	Samsung Internet Android Full support Yes
deltaMode	Chrome Full support 31	Edge Full support 12	Firefox Full support 17	IE Full support 9	Opera Full support 18	Safari Full support 6.1	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 17	Opera Android Full support Yes	Safari iOS No support No	Samsung Internet Android Full support Yes
deltaX	Chrome Full support 31	Edge Full support 12	Firefox Full support 17	IE Full support 9 Notes' Full support 9 Notes' Notes' IE9 supports an old draft of the spec where this value was a long instead of a double.	Opera Full support 18	Safari Full support 6.1	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 17	Opera Android Full support Yes	Safari iOS No support No	Samsung Internet Android Full support Yes
deltaY	Chrome Full support 31	Edge Full support 12	Firefox Full support 17	IE Full support 9 Notes' Full support 9 Notes' Notes' IE9 supports an old draft of the spec where this value was a long instead of a double.	Opera Full support 18	Safari Full support 6.1	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 17	Opera Android Full support Yes	Safari iOS No support No	Samsung Internet Android Full support Yes
deltaZ	Chrome Full support 31	Edge Full support 12	Firefox Full support 17	IE Full support 9 Notes' Full support 9 Notes' Notes' IE9 supports an old draft of the spec where this value was a long instead of a double.	Opera Full support 18	Safari Full support 6.1	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 17	Opera Android Full support Yes	Safari iOS No support No	Samsung Internet Android Full support Yes
Pinch-to-zoom maps to WheelEvent + ctrl key.	Chrome Full support 31	Edge Full support ≤79	Firefox Full support 55	IE ?	Opera ?	Safari No support No	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 55	Opera Android ?	Safari iOS No support No	Samsung Internet Android Full support Yes

Legend

Full support  

Full support

No support  

No support

Compatibility unknown  

Compatibility unknown

See implementation notes.'

See implementation notes.

See also

• wheel event
• Interfaces replaced by this one:
  • Gecko's legacy mouse wheel event object: MouseScrollEvent
  • Non-gecko browsers' legacy mouse wheel event object: MouseWheelEvent

WheelEvent by Mozilla Contributors is licensed under CC-BY-SA 2.5.