Simon Willison’s Weblog

Web design and usability guidelines

Usability.gov’s Research-Based Web Design & Usability Guidelines lose instant credibility for being available only as a 39.2 MB PDF file [ Update: this statement is incorrect—see my correction ], with all of the usability and accessibility problems that brings with it. I’m on a fast connection here so I downloaded them anyway to have a look. There’s actually a lot of good things I can say about them—the document is attractively laid out, the guidelines clear and easy to follow and each is backed up by references to academic research (hence the title). There are however some guidelines with which I completely disagree, in particular the ones in chapter 4, entitled “Hardware and Software”:

4:1 Design for Common Browsers

Guideline: Design, develop and test for the most common browsers.

Comments: Designers should attempt to accommodate ninety-five percent of all users. Ensure that all testing of a website is done using the most popular browsers.

Rubbish. Designers should attempt to accommodate 100% of all users (in as much as content should be accessible to them), which really isn’t difficult if you stick to the standards rather than designing with a particular browser in mind. The 95% statistic is particularly worrying as they link to The Counter.com as a source of browser statistics, which currently shows Internet Explorer as holding 93% of the market.

4:2 Account for Browser Differences

Guideline: Do not assume that all users will have the same browser features, and will have set the same defaults.

Comments: Visually impaired users tend to select larger fonts, and some users may turn off backgrounds, use fewer colors, or use font overrides. The designer should find out what settings most users are using, and specify on the website exactly what assumptions were made about the browser settings.

Great guideline, lousy comment. How does specifying on a site what assumptions were made about the browser settings help anyone? It’s almost like having “best viewed in Internet Explorer at 1024x768 with 32 bit colour” plastered on to the front page. No one is going to change their settings for your site, so telling them what is assumed isn’t going to help them one iota.

Tellingly, the guidelines make no mention of using web standards or validating pages anywhere in the document. While there’s lots of useful stuff in there, this omission (and the clangers highlighted above) mean the overall package should be examined with a critical eye.