Any time you conduct research, you want to have a way to measure the effectiveness of your product or prototype. To do so, use key performance indicators (KPIs), which are critical measures of progress toward an end goal.

When deciding which KPIs to measure for your project, think about the goals of your research and the findings you want to be able to present to your team, or include in your portfolio, after the research concludes. Each KPI is unique, and together, they work to help you measure the success of the user experience you’ve designed.

• Time on task

  • measures how long it takes for a user to complete a task. A task can involve any function within the product you’re designing, such as filling out a form or making a purchase.
  • It’s generally safe to assume that the less time it takes for users to perform a task, the more effective your design is.

• Use of navigation vs. search

  • indicates the number of people who use a website or an app’s navigation, compared to the number of people who use the search functionality.
  • The goal is to help you understand how users interact with the navigation and search functions of your product. Keeping track of your users’ preferences can help you strike a good balance between them in your designs.

• User error rates

  • indicate the parts of a design that cause users to make errors.
  • For example, a user might click on the wrong icon when trying to make a purchase, forget to check a box or submit incorrect information when filling out a form.
  • These errors are not the user’s fault! Instead, user error rates help point to areas where you need to make improvements to the design of the user experience.
  • As a general rule, the lower the number of errors, the better the design.

• Drop-off rates

  • show how many users abandon the experience.
  • This KPI reveals how many users quit before reaching the end of purchase or some other endpoint you’re trying to lead them to. Users might quit using your product if the navigation is difficult to understand.
  • To measure drop-off rates in your own designs, count the number of participants who quit a task or don’t make it to the end of their goal. Then, make changes to your designs to improve the user experience and run a second research study.

• Conversion rates

  • Measure the percentage of users who complete the desired action.
  • To measure the conversion rate for your product, count the number of research study participants who complete a listed action.
  • As a general rule, the higher the conversion rate, the better the design.
  • In addition, comparing the conversion rate from one research study to the next can help you gauge the success of the changes you made to your designs.

• System Usability Scale

  • is a questionnaire that asks participants their opinions about your product; the results are used to measure the usability of your designs.
  • users are asked the extent to which they agree or disagree with 10 statements about the usability of a design.
  • For example, users might be asked to respond to the statement: “I thought the app was easy to use” on a scale from “strongly disagree” to “strongly agree.”

• Net Promoter Score

  • (NPS) is a measure of how loyal users will be to your product or service.
  • Participants rate the question, “Would you recommend this product to a friend or colleague?” on a scale of 0 to 10.
    • Promoters are participants who give a rating of 9 or 10, which means they would recommend your product to others.
    • Passives are participants who give a rating of 7 or 8, which means they are satisfied with your product, but they probably won’t pass it along to friends or colleagues.
    • Detractors are participants who rate from 0 to 6, which means they could warn people away from your product or service.
  • To calculate the NPS, subtract the percentage of detractors from the percentage of promoters. When your NPS is positive, it’s a sign that users are satisfied with your designs.
  • If your NPS is negative, it’s a sign that your user experience might have bugs, be difficult to navigate, or might otherwise cause frustration among users.