Interface Sketch and Responsive Boilerplate are two useful tools to aid in the process of designing a website. Interface Sketch provides free sketch templates designed to help users materialize their website layout ideas, while Responsive Boilerplate bills itself as a minimalist, lightweight cross browser grid system made with only twelve columns and three main classes. CoffeeCup.com also offers a useful website design tool that creates responsive layouts with custom breakpoints by using configurable grid systems.
The sketch templates found on Interface Sketch are available as downloadable PDF files. Users are also able to download and edit the templates to create their own sketch sheets by downloading the templates as SVG files, which can be opened by most mainstream vector drawing programs such as Adobe Illustrator, CorelDraw, and Inkscape.
Due to its grid system made with a limited number of main classes and columns, Responsive Boilerplate claims to have a low learning curve. Responsive Boilerplate is primarily designed for mobile devices. CoffeeCup.com's website design utility tool includes a number of integrated grid systems with customizable column counts and gutter widths. Web Design Ledger has also compiled a list of 10 useful website wireframe design tools including programs such as Mockflow, Pencil Project, and Mockingbird.