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  • Writer's pictureantoniodellomo

KPIs (Key Performance Indicators)

UX design plays a vital role in the overall success of your product. These days companies put a large number of resources into developing UX that is highly functional and innovative. However, how do you know if you’re seeing a positive return on investment (ROI) when it comes to your investments in UX? The answer can be found through the measurements of key performance indicators (KPIs).

After something is made, after people using your product, you are looking back and you are trying to find how effective what you have done is and how the product is performing. This last research allows you to learn about the effectiveness of your UX efforts also in terms of sales, conversion rates. KPIs translate the success factors of your project, product, or company into numbers, bringing successes and failures to light.

User experience metrics are a bit different than metrics used in sales, marketing or finance because they reflect human behavior and attitude. This kind of information is a bit difficult to turn into numbers, but on the other hand, UX KPIs provide great insight into the size and magnitude of usability issues and help easily track their changes through time.

Types of KPI’s

KPI broadly divided into categories such as:

  • Behavioral: How users interact with your product or website, what they are effectively doing.

  • Attitudinal: How users feel, what they say before, during, or after using your product, and how this affects brand perception.

6 UX KPIs You Need To Track

KPIs are a great way to showcase the progress to shareholders and team members who are not necessarily UX professionals and numerical data is more comprehensible and easy to digest. While there are many KPIs you can track, these are the 6 important KPI's that stand above all.


  • Time-on-task: A measure of how long it takes a user to complete a specific task. This is a great way to measure User Experience when being able to complete a task quickly is important to users. Helps you analyze how effective your product is at helping user complete their desired goals.

  • Task success rate: A measure of how many users are able to successfully complete a task. Calculated by dividing the number of successfully completed tasks by the number of attempts.

  • User error rate: This is the number of times a user makes a wrong entry. The UER (User error rate) gives you an idea of how clear and user-friendly your website is.


  • System Usability Scale (SUS): This is a tool with which you can measure the usability of the product. The scale consists of a 10-point questionnaire with five possible answers each, ranging from strongly agree to strongly disagree.

  • Customer satisfaction (CSAT): With this tool helps you to expresses customer satisfaction in a convenient metric. Users/testers are asked: How satisfied are you with (website, product, service, etc.)? The scale usually includes five rating options, ranging from very dissatisfied to very satisfied.

  • Net Promoter Score (NPS): Helps you to measure overall customer loyalty for your brand, products, or services. This works on a scale of 1- 10. If the user selects form 9–10, then they are loyal enthusiasts who would recommend your product. 7–8 are called passive. 0–6 are unhappy people who don’t want to see your product ever again.

KPI and ROI – what’s the difference?

Using ROI and KPI, companies can measure how successful they have been in achieving a particular goal.

The ROI (return on investment) is a purely financial indicator and quantifies how successful a project was in relation to its investment. For example, if a company invests EUR 10,000 in UX activities to improve its online shop and then generates EUR 25,000 more revenue in the following year, this corresponds to an ROI of 150%.

On the other hand, KPIs, are key figures that you can choose or define yourself which translate the success of a project – however, it may be defined – into tangible figures.

While ROI is only a financial indicator, KPIs are relevant for almost all employees of an organization – from call center employees to CEOs – and can be applied to a variety of processes.


UX design processes require constant iterations and improvement. KPIs are tools for UX designers to communicate, research, understand, criticize, and influence. Without KPIs, it is difficult to produce a relevant user experience that serves business goals.


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