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: A number representing 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".

Also inherits methods from its parent interface, CSSNumericValue.

Also inherits 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 Aug 4, 2026 by MDN contributors.