Size Attribute

The size attribute makes the width of the <input> element smaller or larger. The value of this size attribute must be a non-negative number greater than 0. The default value of this attribute is 20.

Example

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <form>
        <label for="username">Username</label>
        <input type="text" id="username" size="11"> 
        <br><br>
        <input type="submit" value="Submit">
    </form>
</body>
</html>

Try it Yourself