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The read-only property returns an integer that represents the number of style declarations in this CSS declaration block.


var num = styles.length;


An integer that provides the number of styles explictly set on the parent of the instance.


The following gets the number of explicitly set styles on the following HTML element:

<div id="div1" style="margin: 0 10px; background-color: #CA1; font-family: monospace"></div>

JavaScript code:

var myDiv = document.getElementById('div1'); var divStyle = myDiv.style; var len = divStyles.length; // 3


Specification Status Comment
CSS Object Model (CSSOM)
The definition of 'CSSStyleDeclaration.length' in that specification.
Working Draft  
Document Object Model (DOM) Level 2 Style Specification
The definition of 'CSSStyleDeclaration' in that specification.

Browser compatibility

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Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)
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Document Tags and Contributors

Contributors to this page: bunnybooboo, Qantas94Heavy
Last updated by: bunnybooboo,