HTML id Attribute

The id attribute specifies a unique id for an HTML element (the value must be unique within the HTML document)."

Definition and Usage

The id attribute specifies a unique id for an HTML element (the value must be unique within the HTML document).

The id attribute is most used to point to a style in a style sheet, and by JavaScript (via the HTML DOM) to manipulate the element with the specific id.

Applies to

The id attribute is a Global Attribute, and can be used on any HTML element.

Element Attribute
All HTML elements id

Example

Example

Use the id attribute to manipulate text with JavaScript:

<html>
<body>

<h1 id="myHeader">Hello World!</h1>
<button onclick="displayResult()">Change text</button>

<script>
function displayResult() {
    document.getElementById("myHeader").innerHTML = "Have a nice day!";
}
</script>

</body>
</html>

Browser Support

Attribute
id Yes Yes Yes Yes Yes