Measuring the Usability Index

  1. Displaying and Downloading the Checklist
  2. Determining the Purpose and Style
  3. Asking the Questions
  4. Answering the Questions


A checklist is a technique for evaluating the attributes that make it easy to find and understand information on a Web site. By writing down measurable attributes based on usability research in a question format, you can track the attributes to use for your own Web site.

To measure the usability index of your Web site is a four-step process.

1. Displaying and Downloading the Checklist

Using your browser, you:

The Excel spreadsheet is the easiest format to use because you can add your own questions and the index is calculated by Excel. For the checklist in HTML format, you have to calculate the index yourself.

2. Determining the Purpose and Style

You can also use the checklist to help you design a Web site. When designing a new Web site, the first questions you should ask yourself is:

For example, the main purpose of the site for this paper is to display the paper and generate interest in checklists. The Web site for this paper is modeled on the simple yet effective style of Jacob Nielson's Web site [11].

3 - Asking the Questions

According to Horton [5], online information should be designed to answer user questions. Our checklists are based on this "asking questions" strategy.

If you download the Excel checklist, you can add and delete questions to better fit the requirements of your own Web site. For example, for our Keevil & Associates site we want to ensure that you can scan information displayed on a small window; therefore, we added the question:

4 - Answering the Questions

You can use the Microsoft Excel spreadsheet to calculate the usability index based on your answers to the questions.

For the checklist calculation, we gave equal weight to each of the questions. Depending on the purpose of the Web site, you can answer the questions as Not Applicable to eliminate the questions that do not apply. For example, for a non-technical site, you can answer all the questions in the Evaluating the Technical Accuracy category as Not Applicable.

We included this four-step process for measuring the usability index to encourage other technical communicators to modify the checklist for their own Web sites. Although the process for developing the checklist is simple, you still need to understand many usability principles. The checklist is a mechanism for researching the published usability principles and using them to enhance your own Web site.