WheelEvent - Web APIs

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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  a:hover text { fill: #0095DD; pointer-events: all;}

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

Browser compatibility

	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.