Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.
Non-standard: This feature is not standardized. We do not recommend using non-standard features in production, as they have limited browser support, and may change or be removed. However, they can be a suitable alternative in specific cases where no standard option exists.
The primitiveType read-only property of the CSSPrimitiveValue interface represents the type of a CSS value.
Note: This property was part of an attempt to create a typed CSS Object Model. This attempt has been abandoned, and most browsers do not implement it.
To achieve your purpose, you can use:
An unsigned short representing the type of the value. Possible values are:Constant Description CSS_ATTRThe value is an attr() function. The value can be obtained by using the getStringValue() method.CSS_CMThe value is a <length> in centimeters. The value can be obtained by using the getFloatValue() method.CSS_COUNTERThe value is a counter or counters function. The value can be obtained by using the getCounterValue() method.CSS_DEGThe value is an <angle> in degrees. The value can be obtained by using the getFloatValue() method.CSS_DIMENSIONThe value is a <number> with an unknown dimension. The value can be obtained by using the getFloatValue() method.CSS_EMSThe value is a <length> in em units. The value can be obtained by using the getFloatValue() method.CSS_EXSThe value is a <length> in ex units. The value can be obtained by using the getFloatValue() method.CSS_GRADThe value is an <angle> in grads. The value can be obtained by using the getFloatValue() method.CSS_HZThe value is a <frequency> in Hertz. The value can be obtained by using the getFloatValue method.CSS_IDENTThe value is an identifier. The value can be obtained by using the getStringValue() method.CSS_INThe value is a <length> in inches. The value can be obtained by using the getFloatValue() method.CSS_KHZThe value is a <frequency> in Kilohertz. The value can be obtained by using the getFloatValue() method.CSS_MMThe value is a <length> in millimeters. The value can be obtained by using the getFloatValue() method.CSS_MSThe value is a <time> in milliseconds. The value can be obtained by using the getFloatValue() method.CSS_NUMBERThe value is a simple <number>. The value can be obtained by using the getFloatValue() method.CSS_PCThe value is a <length> in picas. The value can be obtained by using the getFloatValue() method.CSS_PERCENTAGEThe value is a <percentage>. The value can be obtained by using the getFloatValue() method.CSS_PTThe value is a <length> in points. The value can be obtained by using the getFloatValue() method.CSS_PXThe value is a <length> in pixels. The value can be obtained by using the getFloatValue() method.CSS_RADThe value is an <angle> in radians. The value can be obtained by using the getFloatValue() method.CSS_RECTThe value is a rect() function. The value can be obtained by using the getRectValue() method.CSS_RGBCOLORThe value is an <color>. The value can be obtained by using the getRGBColorValue() method.CSS_SThe value is a <time> in seconds. The value can be obtained by using the getFloatValue() method.CSS_STRINGThe value is a <string>. The value can be obtained by using the getStringValue() method.CSS_UNKNOWNThe value is not a recognized CSS2 value. The value can only be obtained by using the cssText attribute.CSS_URIThe value is a <url>. The value can be obtained by using the getStringValue() method.
const cs = window.getComputedStyle(document.body);
const cssValue = cs.getPropertyCSSValue("color");
console.log(cssValue.primitiveType);This feature was originally defined in the DOM Style Level 2 specification, but has been dropped from any standardization effort since then.
It has been superseded by a modern, but incompatible, CSS Typed Object Model API that is now on the standard track.