You do not always need to invite users for tests to find out how they use your app, website, or store. You can learn a lot by observing KPIs. What are KPIs, and how do you measure them? We will try to explain that in today’s article.


KPIs stand for Key Performance Indicators. These are metrics allowing us to determine the goal of our work and assess if we are moving in the right direction. Every organization sets their own KPIs corresponding to its business model and strategy. It is not worth following indicators of other companies, unless they have a similar business model, target group, and are in a similar business situation to our organization, e.g. they are working on ways to increase sales via their website.

What is more, every department of an organization has their own KPIs, which also support the main business objectives of the organization. For e.g. the support department can adopt decreasing the average time of solving a specific customer problem (perhaps problems with signing in) to be its performance indicator.  On the other hand, the marketing department can assume that their KPI is the increased conversion due to the newsletter, as it supports the business objective to increase the number of leads. What about the design department? How do UX and UI designers measure their efficiency?

What metrics to focus on in a design department?

The basic UX metric can be customer satisfaction improvement. Unfortunately, without sending cyclic surveys or talking to customers directly, it is difficult to verify if satisfaction has improved. There are other metrics allowing to positively influence the improvement of general customer satisfaction, also originating in the design work: adding new functionalities, redesigning the page, improving customer path, and other investments in UX. Such metrics should be constantly followed and reported in equal intervals, e.g. once per month. What metrics are these?

Usually, designers set KPIs related to achieving an objective by a user. This can be finding a product, filling out a form, or correcting personal details. The design team uses quantitative and qualitative data to measure KPIs. Data is collected by using tools like Google Analytics, Fullstory, Hotjar, surveys, or by talking to users. What KPIs are popular among designers?

UX KPIs for web or mobile apps

Task time

Some UX teams consider the time required to complete a task as one of their KPIs. The shorter the time, the more effective the work. Develop benchmarks for this indicator and decide if a shorter time to task completion can indicate user experience efficiency. There are situations, in which this would not be a good indicator – everything depends on the product, the task, or the user group.

Error rate

Users sometimes make errors when using a digital product. This is completely normal. The problem starts if the error rate gets very high. If you observe a high error rate, use an analytic tool at some product view and analyze the potential causes. A low error rate indicates UX efficiency.

Task success rate

Does every attempt at completing a task end with success? Before you set task completion as KPI for UX, think if you have clearly defined what task completion constitutes. The task may be leaving an review about the product. If the user does not meet obstacles preventing them from completing a task, this points to good UX.

Task abandonment rate

As marketing measures the rejection factor, a UX specialist pays attention to how many percent of users abandoned a task before completing it. This metric points out mistakes to be discovered with internet analytics or UX surveys. It is worth learning the cause of the mistakes, as it disturbs UX efficiency.

UX KPIs for a website or e-commerce

Interaction depth

Checking interaction depths, i.e. the number of pages displayed during one visit e.g. on a page is also a good way, especially if we care about measuring the engagement of our users. Perhaps mobile users are less engaged than the ones browsing through our page on a desktop. This KPI is worth following.

Searching and navigation

In some projects (especially in e-commerce), UX specialists watch search engine use and navigation. They set KPIs on this basis. If users use the page’s search engine to find easily available information or subpages, it is worth improving navigation. It may turn out it is not clear enough.

Conversion rate

Everyone needs to determine individually what a conversion is on a website or store. Usually, conversions are divided into micro-conversions and macro-conversions. Micro-conversions are actions bringing visitors closer to becoming our customers. These can be making purchases, signing up for a webinar, or a newsletter. Macro-conversion is the main objective of our business’ presence on the internet, e.g. selling our products. Following the conversion factor can provide us with insight into whether our page is optimized for conversion, or if we should improve it.

When we have the time to interview users

If we have the time and budget for cyclic interviews with the people using our solution, we can decide to measure customer satisfaction and their subjective experiences related to our project. This will allow us to discover if our product, e-commerce store, or the page has good UX. Remember that the user evaluation will be subjective, and if we do not ask leading questions, we will not be able to draw qualitative conclusions. Nevertheless, it is worth asking questions. What tools can be useful for that?

Net Promoter Score (NPS)

NPS is a survey of customer satisfaction and mainly of the willingness to recommend your solution to others. You provide a scale from 1 to 10 and ask the user to indicate if they will recommend your product, assuming that 10 means definitely yes, and 0 means definitely no. Scale interpretations vary, but usually, the average of 6 and more is considered a great result. To measure only NPS, you can use Hotjar, which allows you to install a pop-up with a question about customer satisfaction with a scale and comment. Unfortunately, NPS without context will not be of any use, therefore, it is better if it is a part of a more developed survey.

System Usability Score (SUS)

System Usability Score is a tool for measuring product usability. It consists of 10 statements. Under each statement, there is a scale from “Definitely agree” to “Definitely disagree”. The user needs to select one point on the scale corresponding to their preferences. If we connect SUS to a usability survey, we have a chance to gain great insight into our product. Some design teams use this as one of the KPIs.

How to use KPIs?

Let’s say that you are developing an app to teach programming, and your business objective is to increase the number of registrations, which, despite numerous app downloads, leaves a lot to be desired. What can you do to improve this metric? Perhaps it will be enough to work on onboarding in the app. How can you check if your action has had any effect? It is enough to check if the number of registrations has increased after implementing the changes.

The selected KPI can signal that something requires improvement. Let’s say you see that the number of abandoned carts has increased drastically. Analyzing data from Hotjar or other tools to track traffic on the page, you notice that a significant number of users click the marketing banner which pops up at an inappropriate time and breaks the purchase path. It is enough to correct this element and the conversion will return to the previous state.

When is it good to determine KPIs for UX?

A good practice is to set KPIs at the very beginning of developing one’s business. This is mostly the stage to determine business goals and plan a strategy. The KPIs you set will determine which actions of the design team will be a priority, and which will need to wait for their turn. KPIs should support your business goals, therefore, when talking about business goals with the board, you should decide what key metrics will let you say that an objective has been achieved.

Additionally, when implementing changes in a product, it is worth taking another look at all the metrics and estimating if KPIs can tell us if our project can be considered a success because it supports the objectives, or if it is more likely to fail. We can always select additional metrics to illustrate the status of our project. For example, what metrics are indicative of a well-performing form, that is, one that gets more people to complete it. Why is it important? Because our objective is to increase the number of leads. Let’s designate a person responsible for tracking and reporting on these metrics.

Suppose our company offers a B2B web application. In such a situation, it is mainly the salespeople who are held accountable for sales results. Suppose that we make a decision to redesign one of the main views. After implementing the changes, it turns out sales have decreased significantly. Our sales KPI leaves a lot to be desired. In this case, sales improvement does not depend mainly on the sellers, but on the design team, as, after a short inspection, we can see that new users have problems with understanding how the app works.

If we had agreed on which metrics to pay attention to when starting the project, the problem would have been solved quite efficiently.

What KPI should not look like?

Today, we are able to measure almost everything. Unfortunately, this does not mean that we should pay attention to every metric we have access to. What is more, metrics are not always related to the work of a designer, and some of them can give us a false sense of control. How to recognize such metrics?

E.g. the number of new users on a page is a very useful metric for the marketing department. If the marketing additionally measures traffic sources, they can see which marketing activities impact the business. Unfortunately, this will not say anything about user behavior to the designer. The rejection factor is similar – the designer can pay attention to this metric, however, it will not give them a full picture of what is going on on the page and why people are leaving it. Perhaps this does not depend on the work of the designer, but e.g. on mistakes in preparing a marketing campaign. A definitely better metric is the page error factor.

To avoid setting a wrong KPI, pay attention to what the board members want to achieve and what business objectives they anticipate. Set KPIs based on the strategy they adopted. Apart from business value, there is one additional advantage – reaching KPIs will make it easier to convince the board to other investments in UX.