This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The computedStyleMap() method of the Element interface returns a StylePropertyMapReadOnly interface which provides a read-only representation of a CSS declaration block that is an alternative to CSSStyleDeclaration.


var stylePropertyMapReadOnly = element.computedStyleMap()



Return value

A StylePropertyMapReadOnly interface.


We start with some simple HTML: a paragraph with a link, and a definition list to which we will add all the CSS Property / Value pairs.

   <a href="https://example.com">Link</a>
<dl id="regurgitation"></dl>

We add a little bit of CSS

a {
  --color: red;
  color: var(--color);

We add JavaScript to grab our link and return back a definition list of all the CSS property values using computedStyleMap().

// get the element
const myElement = document.querySelector('a');

// get the <dl> we'll be populating
const stylesList = document.querySelector('#regurgitation');

// Retrieve all computed styles with computedStyleMap()
const allComputedStyles = myElement.computedStyleMap();

// iterate thru the map of all the properties and values, adding a <dt> and <dd> for each
for (const [prop, val] of allComputedStyles) {
	// properties
	const cssProperty = document.createElement('dt');

	// values
	const cssValue = document.createElement('dd');

In browsers that support computedStyleMap(), you'll see a list of all the CSS properties and values. In other browsers you'll just see a link.

Did you realize how many default CSS properties a link had? Update the 'a' to the 'p', and you'll notice a difference in the margin-top and margin-bottom default computed values.


Specification Status Comment
CSS Typed OM Level 1
The definition of 'computedStyleMap()' in that specification.
Working Draft Initial definition.

Browser compatibility

BCD tables only load in the browser