Nowadays – when building a website – one is confronted with a number of different sizes and browsers that is daunting.* Plus, with mobile adoption skyrocketing, the diversity of mobile devices on the market doesn’t fail to grow exponentially. Thank god / the vivid web design community no custom coding is needed for each device or screen size with current responsive web design frameworks and testing tools.

We’ve selected 6 tools and libraries to get you started with responsive web design:

Bootstrap

Built at Twitter by Mark Otto and Jacob Thornton, Bootstrap offers an easy configurable CSS front-end framework. Bootstrap was made to not only look and behave great in the latest desktop browsers (as well as IE7!), but also in tablet and smartphone browsers with a 12-column responsive grid, dozens of components, JavaScript plugins, typography, form controls, and has a web-based Customizer. Bootstrap comes in different shapes and forms, like Google BootstrapRetriever Bootstrap and the super fun (and equally ugly) Geo Bootstrap.