CSSUnitValue

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The CSSUnitValue interface of the CSS Typed Object Model API represents values that contain a single unit type.

For example, the value 42px (a <dimension>) would be represented by a CSSNumericValue.

Constructor

CSSUnitValue.value: Returns a double indicating the number of units. For a CSSNumericValue representing 42px, this would be 42.
CSSUnitValue.unit: Returns a string indicating the type of unit. For a CSSNumericValue representing 42px, this would be "px".

The interface may also inherit methods from its parent interface, CSSNumericValue.

The interface may also inherit methods from its parent interface, CSSNumericValue.

The following shows a method of creating a CSSPositionValue from individual CSSUnitValue constructors.

let pos = new CSSPositionValue(
  new CSSUnitValue(5, "px"),
  new CSSUnitValue(10, "px"),
);

Specification
CSS Typed OM Level 1 # simple-numeric

This page was last modified on Jul 31, 2026 by MDN contributors.