is archived and no longer updated

External links may not function and information on the site may be out of date. Visit for current information.

Usability Evaluation Basics

Usability Evaluation focuses on how well users can learn and use a product to achieve their goals. It also refers to how satisfied users are with that process. To gather this information, practitioners use a variety of methods that gather feedback from users about an existing site or plans related to a new site.

What is Usability?

Usability refers to the quality of a user's experience when interacting with products or systems, including websites, software, devices, or applications. Usability is about effectiveness, efficiency and the overall satisfaction of the user.

It is important to realize that usability is not a single, one-dimensional property of a product, system, or user interface. ‘Usability’ is a combination of factors including:

  • Intuitive design: a nearly effortless understanding of the architecture and navigation of the site
  • Ease of learning: how fast a user who has never seen the user interface before can accomplish basic tasks
  • Efficiency of use: How fast an experienced user can accomplish tasks
  • Memorability: after visiting the site, if a user can remember enough to use it effectively in future visits
  • Error frequency and severity: how often users make errors while using the system, how serious the errors are, and how users recover from the errors
  • Subjective satisfaction: If the user likes using the system

What are the Evaluation Methods and When Should I Implement Them?

The key to developing highly usable sites is employing user-centered design. The expression, “test early and often”, is particularly appropriate when it comes to usability testing. As part of UCD you can and should test as early as possible in the process and the variety of methods available allow you to assist in the development of content, Information architecture, visual design, interaction design and general user satisfaction.

Opportunities for testing include:

Any one or a combination of these tests will radically improve the usability of your site, system or application.

Working with Data from Testing

Usability evaluations can capture two types of data: qualitative data and quantitative data.  Quantitative data notes what actually happened.  Qualitative data describes what participants thought or said.

Once you have gathered your data, use it to:

  1. Evaluate the usability of your website
  2. Recommend improvements
  3. Implement the recommendations
  4. Re-test the site to measure the effectiveness of your changes.