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HTMLElement: style property

The read-only style property of the HTMLElement returns the inline style of an element in the form of a live CSSStyleDeclaration object that contains a list of all styles properties for that element with values assigned only for the attributes that are defined in the element's inline style attribute.

Shorthand properties are expanded. If you set style="border-top: 1px solid black", the longhand properties (border-top-color, border-top-style, and border-top-width) are set instead.

This property is read-only, meaning it is not possible to assign a CSSStyleDeclaration object to it. Nevertheless, it is possible to set an inline style by assigning a string directly to the style property. In this case the string is forwarded to CSSStyleDeclaration.cssText. Using style in this manner will completely overwrite all inline styles on the element.

Therefore, to add specific styles to an element without altering other style values, it is generally preferable to set individual properties on the CSSStyleDeclaration object. For example, you can write element.style.backgroundColor = "red".

A style declaration is reset by setting it to null or an empty string, e.g., elt.style.color = null.

Note: CSS property names are converted to JavaScript identifier with these rules:

If the property is made of one word, it remains as it is: height stays as is (in lowercase).
If the property is made of several words, separated by dashes, the dashes are removed and it is converted to camel case: background-attachment becomes backgroundAttachment.
The property float, being a reserved JavaScript keyword, is converted to cssFloat.

The style property has the same priority in the CSS cascade as an inline style declaration set via the style attribute.

Value

A live CSSStyleDeclaration object.

Examples

Getting style information

The following code snippet demonstrates how the values obtained using the element's style property relates to the style set on the HTML attribute:

html

<!doctype html>
<html lang="en-US">
  <body style="font-weight:bold">
    <div style="border-top: 1px solid blue; color:red" id="elt">
      An example div
    </div>
    <pre id="out"></pre>
  </body>
</html>

const element = document.getElementById("elt");
const out = document.getElementById("out");
const elementStyle = element.style;

// We loop through all styles (for…of doesn't work with CSStyleDeclaration)
for (const prop in elementStyle) {
  if (Object.hasOwn(elementStyle, prop)) {
    out.textContent += `${
      elementStyle[prop]
    } = '${elementStyle.getPropertyValue(elementStyle[prop])}'\n`;
  }
}

Note font-weight is not listed as a value for elementStyle as it is not defined within the style attribute of the element itself. Rather, it is inherited from the definition on its parent. Also note that the shorthand border-top property, defined in the style attribute, is not listed directly. Rather, it is replaced by the three corresponding longhand properties (border-top-color, border-top-style, and border-top-width).

Specifications

Specification
CSS Object Model (CSSOM) # dom-elementcssinlinestyle-style

Browser compatibility

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	WebView Android	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet
`style`	1	12	1	5.5	8	3	4.4	18	4	10.1	1	1.0

Value

Examples

Getting style information

Specifications

Browser compatibility

See also