Packed house for the Packed house for the “UX Prototyping Tools” session at SXSW.

If a website takes four seconds or more to load, 25-percent of visitors will abandon the site before it fully loads. We have very little time to make impressions on site visitors and convince them to stay and engage with us.

This might explain why there was no shortage of interest in a discussion at South by Southwest today about user experience prototyping when designing for websites. The room was packed and still had a line down the hall with people hoping someone would walk out so they could walk in their place. Why the interest? And what is website prototyping, anyway?

Prototyping is the step between wireframe and design. It is essentially a functional wireframe that shows users how the site will work. If wireframes are the blueprints of your new house, the prototype is a 3-D model without any of your selected finishes showing yet. A prototype is stripped of color, uses generic fonts and only boxes represent images. And they are perfect for user testing to understand what works and what doesn’t for moving a user through a site.

The SXSW session audience was mostly made up of strategists and designers who use prototype tools themselves before turning files over to the development team. This saves time as the developers don’t get far down the coding process before someone figures out the users won’t understand how a feature works.

While no one prototyping won the hearts of every audience member, the most mentioned and favorited were:

Some of these tools allow for testing fully designed websites, while others are limited to only wireframes. And a couple allow for testing on mobile devices.

Regardless of the tool used, it was clear that prototyping before developing is becoming more commonplace as user experience determines whether a customer will stay or leave your website.