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web api instance property

WheelEvent: deltaX property

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The WheelEvent.deltaX read-only property is a double representing the horizontal scroll amount in the deltaMode unit.

You must check the deltaMode property to determine the unit of the deltaX value. Do not assume that the deltaX value is specified in pixels. Some browsers, for compatibility reasons, may return different units for the deltaX value depending on whether deltaMode has been accessed, to accommodate for websites not explicitly checking the deltaMode property.

Value

A number.

Examples

const syntheticEvent = new WheelEvent("syntheticWheel", {
  deltaX: 4,
  deltaMode: 0,
});

console.log(syntheticEvent.deltaX);

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also