CSS dimension width pixel
<html>
<head>
<style type="text/css">
img
{
width: 300px
}
</style>
</head>
<body>
<img src="bird.jpg" width="150" height="112" />
</body>
</html>
<head>
<style type="text/css">
img
{
width: 300px
}
</style>
</head>
<body>
<img src="bird.jpg" width="150" height="112" />
</body>
</html>
Result
