Resize Images Using CSS

This is an older CSS trick that is worth repeating. Back in the days, resizing images was done via HTML height and width options. Here’s an example below. We will resize the image to 100 x 100 pixels.


<img src="example.jpg" width="100" height="100" alt="example" />

The problem with this approach is, first, we will lose image quality when resizing regardless of which direction we go, either up or down. The resized image is never going to be as good as the original. Second, there’s a good chance the image will NOT be proportioned. We have to be constantly be aware of image ratios when resizing images.


So, here comes CSS to the rescue. We will assign a class called “image” to our image.

<img class="image" src="example.jpg" alt="example" />

Next, we will apply CSS to our “image” class.

.image { width: 400px;height : auto; }
.image { width: auto;height : 600px; }

The result is, a well-porportioned image that is never going to be wider than 400px or taller than 600px. In addition, we maintain the standard dimension for all images using the “image” class.