Testing Responsive Web Design using Mozilla Firefox

If you want to test Responsive Web Design techniques against your website to make sure it accommodates various different screen sizes, then Mozilla Firefox offers a nice set of tools to allow you to do this.

1. Hit the F12 button to launch Firefox's Developer Tools
2. In the upper right hand corner, you will find a button for "Responsive Design Mode"
3. Click on the "Responsive Design Mode" button
4. You will now see a screen that allows you to select various different screen sizes for you to test your website!