At a glance your website may still look tasty, but how do you know if its expiration date has passed? Usability problems can easily sneak in during a well-intentioned design phase or the ongoing post-launch updates. What may seem like charming quirks to you could be causing real problems for your visitors and, ultimately, your bottom line.

It doesn't take a lot of time or money to give your site a reality check. Just take a step back and look at it with a fresh perspective. Don't be afraid to take a big whiff. You might be surprised by the usability problems that are right under your nose.

Enter the heuristic* evaluation. It's a site analysis based on Jakob Nielsen's 10 Usability Heuristics, which are rules of thumb for your site's user interface design:

• Visibility of system status: Keep users informed about what's going on through appropriate feedback within reasonable time.
• Match between system and the real world: Speak the users' language with familiar words, phrases and concepts rather than system-oriented terms.
• User control and freedom: Users often choose system functions by mistake and need clearly marked "emergency exits."
• Consistency and standards: Don't make users wonder whether different words, situations, or actions mean the same thing.
• Error prevention: Even better than good error messages is a careful design which prevents a problem from occurring in the first place.
• Recognition rather than recall: Minimize the user's memory load by making objects, actions, and options visible.
• Flexibility and efficiency of use: Accelerators — unseen by the novice user—may often speed up the interaction for the expert user.
• Aesthetic and minimalist design: Dialogues should not contain information which is irrelevant or rarely needed.
• Help users recognize, diagnose, and recover from errors: Express error messages in plain language, precisely indicate the problem, and constructively suggest a solution.
• Help and documentation: Help should be easy to search, focused on the user's task, list concrete steps to be carried out, and not too large.

How does it work?
The test method is quick to learn and can yield great results with as few as three people. Here's an overview:

1. Decide which portion(s) of your site to evaluate. You may not need to analyze your entire web presence. Has your online store been underperforming? Are your form submissions down? Focus your effort on areas that need an immediate boost.
2. Identify (or hire) your testers. Different people use sites in different ways. Three to five usability experts can find a wide range of problems without a lot of wrangling. If you don't have experts in your organization, bring them in on contract. It's also possible to bring web-savvy internal folks up to speed with good coaching.
3. Conduct the test. Sit everybody down at separate computers for a few hours and have them document their findings. Don't let them chat; each tester should experience the site without another person's bias.
4. Consolidate the results. Aggregate the results of each tester into a single report with the findings grouped under their corresponding heuristics.

Depending on your test criteria, it's possible to run the entire evaluation in as few as 10 hours. Then it's time to hang out with your designers and decide how to interpret the results.

I've got a small budget. Is every problem worth fixing?
In a word, no. Figure out what it will cost to fix each problem versus how much you think you'll gain (via increased revenue, profit, productivity or brand value) by doing so. Then you can decide which ones pass budget muster.

Next, group your problems by severity so you can fix them in priority order. Seems reasonable enough, but how do you know which problems are mild-mannered and which will eat your users for breakfast? Nielsen's sage advice is that the severity of a usability problem is the combination of three factors:

• The frequency with which the problem occurs: Is it common or rare?
• The impact of the problem if it occurs: Will it be easy or difficult for the users to overcome?
• The persistence of the problem: Is it a one-time problem that users can overcome once they know about it or will users repeatedly be bothered by the problem?

Can you give me an example?
Let's say your registration form includes some required fields. Submitting the form with those fields left blank results in error messages displayed in a list at the top of the screen, instead of next to or below the fields to which the error messages apply. Because this forces users to scroll up and down to understand which fields are in error, it's a violation of the “Recognition rather than recall” heuristic.

Should you fix it? It's certainly worth evaluating in more detail. Test your changes to see if they increase your form conversion rate.

Sounds too easy. What's the catch?
What heuristic evaluation doesn't tell you is HOW to solve problems you find. Categorizing your findings within Nielsen's framework gives you a starting point but you'll have to figure out the particulars on your own. If you hired usability experts on contract, consider keeping them around for this part of the process.

You also won't get far trying to apply this method to a simple “brochureware” site with no functionality. Most of the guidelines are aimed squarely at identifying issues with user interactions. Heuristics won't tell you if your hot pink color palette gives visitors a headache.

Finally, this method isn't guaranteed to surface 100% of problems. Ironically, the rigid structure that helps ferret out certain issues can cause others to be overlooked if they don't fit neatly into a category. To get the most mileage out of a heuristic evaluation, try to employ seasoned usability professionals as testers.

And next time, the source of that funky smell won't be your website.

Have you had success (or not) with heuristic evaluations? Tell us about your experience. Need a heuristic evaluation of your site? Contact us to talk about how we can help.

* Pronounced "hyoo-ris-tik"