Responsive images are images that scale nicely to fit any browser size.
Using the width Property
If the CSS width property is set to 100%, the image will be responsive and scale up and down:
Responsive Image
When the CSS width property is set in a percentage value, the image will scale up and down when resizing the browser window. Resize the browser window to see the effect.
Example
<img src="/images/cat.jpg" style="width:100%;">
Notice that in the example above, the image can be scaled up to be larger than its original size. A better solution, in many cases, will be to use the max-width property instead.
<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
</head>
<body>
<h2>Responsive Image</h2>
<p>When the CSS width property is set in a percentage value, the image will scale up and down when resizing the browser window. Resize the browser window to see the effect.</p>
<img src="/images/cat.jpg" style="width:100%;">
</body>
</html>
