The length read-only property of the CSSUnparsedValue interface returns the number of items in the object.

An integer.

In this example we employ the CSSUnparsedValue() constructor, then query the length:

const values = new CSSUnparsedValue(["1em", "#445566", "-45px"]);

console.log(values.length); // 3

• CSSUnparsedValue()
• CSSUnparsedValue.entries
• CSSUnparsedValue.forEach
• CSSUnparsedValue.keys
• CSSUnparsedValue.values
• Using the CSS Typed OM
• CSS Typed Object Model API