HTML class Attribute
Example
Use of the class attribute in an HTML document:
<html>
<head>
<style>
h1.intro {
color: blue;
}
p.important {
color: green;
}
</style>
</head>
<body>
<h1 class="intro">Header 1</h1>
<p>A paragraph.</p>
<p class="important">Note that this is an important paragraph. :)</p>
</body>
</html>
Try it Yourself »
More "Try it Yourself" examples below.
Definition and Usage
The class attribute specifies one or more class names for an element.
The class attribute is mostly used to point to a class in a style sheet.
However, it can also be used by a JavaScript (via the HTML DOM) to make changes
to HTML elements with a specified class.
Browser Support
| Attribute | |||||
|---|---|---|---|---|---|
| class | Yes | Yes | Yes | Yes | Yes |
Syntax
<element class="classname">
Attribute Values
| Value | Description |
|---|---|
| classname | Specifies one or more class names for an element. To specify multiple classes, separate the class names with a space, e.g. <span class="left important">. This allows you to combine several CSS classes for one HTML element.
Naming rules:
|
More Examples
Example
Add multiple classes to one HTML element:
<!DOCTYPE html>
<html>
<head>
<style>
h1.intro {
color: blue;
text-align: center;
}
.important {
background-color: yellow;
}
</style>
</head>
<body>
<h1 class="intro important">Header 1</h1>
<p>A paragraph.</p>
</body>
</html>
Try it Yourself »
Example
Using JavaScript to add a yellow background color to the first element with class="example" (index 0).
let x = document.getElementsByClassName("example");
x[0].style.backgroundColor = "yellow";
Try it Yourself »
Example
Using JavaScript to add the "mystyle" class to an element with id="myDIV":
document.getElementById("myDIV").classList.add("mystyle");
Try it Yourself »
Related Pages
HTML Tutorial: HTML Attributes
CSS Tutorial: CSS Syntax
CSS Reference: CSS .class Selector
HTML DOM Reference: HTML DOM getElementsByClassName() Method
HTML DOM Reference: HTML DOM className Property
HTML DOM Reference: HTML DOM classList Property
HTML DOM Reference: HTML DOM Style Object
