The 5 best KPIs for UX Design

ux design

Why am I talking about KPIs for UX?

Today, it is beyond dispute that UX design can be crucial to the success or failure of a product. Therefore, our work as product designers, UX experts, UI designers, and UX researchers is important. But how can we back up what we do with facts, check the success of our work, and correct course in iterations if needed?

One way is to measure our work and thus the user experience.

📊 What are KPIs?

KPI is the abbreviation for key performance indicator. KPIs are therefore measurement figures that express how successfully or frequently a particular thing is done or how often an undesirable error occurs.

🧮 Why should you measure KPIs?

KPIs summarise the result of your data. Clear data and results make it much easier for you to assess the success of your measures for yourself, but also to communicate them to your stakeholders.

KPIs therefore help you to check whether you have already achieved the defined UX goals or are at least on the right path towards them. If this is not the case, with measurable KPIs you have a good instrument to correct your measures and if everything is working well, you can use KPIs to make your success visible.


⏱ Time on Task

This is the time a user needs to complete a task. Since time-consuming software is often unsatisfying, the shorter this time is, the better. The average of all times of the observed users is commonly used for evaluation.

✅ Task Success Rate

Here we’re talking about the percentage of users who successfully complete a defined task. Examples of this would be when users manage to complete the payment process for an online order or find a certain product in the online shop and add it to the shopping cart. In order to measure the Task Success Rate, a task must always have a precisely defined goal that is achieved at the end, or not.

❌ User Error Rate

The error rate provides information about how often users make an error on the way to a defined goal. However, it must be defined what is considered as an error so that a proper evaluation can take place. In contrast to the Task Success Rate, the User Error Rate should be as low as possible.

↗️ Conversion Rate

Most people are more familiar with the conversion rate from marketing, but it can provide important information about the user experience or usability. When users buy products in an online shop or sign up for a newsletter on a landing page, this also is expressed through the conversion.

🔎 Navigation vs. Search

The ratio of users who use the navigation versus the search function to complete a task. With this KPI, it is usually important that the proportion of users who use the navigation is higher, as this usually indicates better usability.

Insights on KPIs for UX

As you see there are many different ways to measure user behavior and thus measure the success of user experience.

Which KPIs have you ever used before to measure user experience? Or do you know even more KPIs? I would love to hear about it. 💬Feel free to reach out on instagram or LinkedIn to share your thoughts.