Usability testing - what and why?

In this handbook we detail everything related to usability and user testing. We zoom in deeper into what user testing entails, why it is important, which variants are available and how you can get started.

In the chapters that follow, we discuss usability testing, recruiting respondents, how many respondents you need as well as analyze usability testing.

What is usability?

Usability is the degree to which a consumer can use a product in his own way without being met with obstacles, doubt or questions. With a user-friendly product, applicability and usage is smooth and frustration eliminated.

What is usability testing?

Usability testing - also called user testing - is the performance of certain tasks by respondents. Here, respondents who belong to the target group of the product perform a number of pre-prepared tasks. The usability test is recorded on camera, while the respondent reviews and gives feedback when he or she finds it necessary. 

This makes it clear why certain functionalities do or do not work - and that translates into a list of concrete action points to make the customer experience (even) better. You record the entire process of usability testing with a usability test plan.

Usability Test Example

The five biggest advantages of usability testing

For every phase in the development process of a website or app, testing with real users is of great value.

  • Discover what users encounter. Convenience serves people, now more than ever. When users want to order a product but the ordering process does not work, they order it from the competitor with three clicks. That leaves the owner of the webshop with one question: why did the user abandon its shopping cart? Through user testing you discover the frustrations of your user audience that would normally go unnoticed, providing you the advantage of knowing who your user is, how they want to receive your product, and how you need to provide it.
  • A better end product with prototype testing. Save time and money by conducting usability testing during the development process. Is it clear what they can do with the app or website? What do they encounter? What would they use it for? By collecting and processing this feedback during the development process, you build a product that better suits the end user.      
  • Create empathy for the end user. It often occurs that a team who have been working a long time on a project find it increasingly difficult to empathize with the end user, because they know the product inside out as an expert and no longer a first time user. User testing forces you to see the product through the eyes of the end user, which gives you a lot of valuable information for the rest of the development process.      
  • Valuable addition to quantitative data. Tools such as Google Analytics and Hotjar show what users do, but not why they do it.. A heatmap can show you that users are dropping out during the ordering process, but not why users are still considering. Usability testing removes that uncertainty and provides insight into how the ordering process can be improved.      
  • A better product for everyone. When you have just launched your product, or have been in the market for some time, you can find out by testing to what extent the product meets expectations. Is something missing in the interface? Do we lose money by having inefficiently arranged the ordering process?     

A better user experience pays off

The ultimate goal of usability testing is therefore to make the experience as good as possible for the user. Various studies have shown that a better user experience can have a huge positive effect on business operations. The five biggest advantages of user testing are:

Is it usability testing or user testing?

You may have noticed that different terms are used for conducting usability tests. The most common variants are user testing and usability testing.

Some UX researchers state that the primary purpose of user testing is to find out if potential users need a certain product or service. You should therefore do user testing prior to development. If you are in that phase yourself, then we highly recommend reading The Mom Test for identifying users' needs.  

Usability testing, on the other hand, would then be conducting usability tests with respondents.

However, it still remains a grey area and both terms are being used interchangeably. Nine times out of ten you will be able to grasp the meaning from the context in which the terms are used. So, feel free to use whatever time you like the most! 

Different types of usability testing

There are different ways to test a website with real users, below we explain the four most common variants. You can read more about when you should use each type of usability testing best here: when to use what type of usability testing?

In a usability lab

By taking the tests in a usability lab you have maximum control over the equipment that is used and you can respond quickly when there are technical problems. The biggest disadvantage is that the user is not in their natural environment, which influences the answers and makes them less honest. It also costs more time and money to recruit users and have them travel to the usability lab.

Remote / Online

A remote usability test, means that the user can complete the test online. In practice, this often means that this is done from home. The biggest advantage is that the user takes the test in their natural environment, which leads to more honest feedback.



This form of user testing is also called moderated user testing. The moderator guides the test session from start to finish. The test can take place both face-to-face and online. When the test takes place online, the moderator uses an online tool to communicate with the users. 

The biggest advantage is that a moderator can ask more in-depth questions and can collect extra data to better understand why the user performs certain actions. On the other hand, an inexperienced moderator may affect questions which can in turn influence the results of the research. If this happens, it will have a negative effect on the reliability of the results - something that you logically want to prevent.


This type of user test is also referred to as unmoderated usability testing, whereby the usability test takes place without supervision. Unmoderated usability tests are almost always carried out remotely.

The biggest advantage of testing without a moderator is that the environment in which the user would normally use the app or website is simulated as much as possible. In real life there is of course no moderator next to the customer to guide them through the ordering process.

With unmoderated remote usability testing, also known as remote unmoderated usability testing, the quality must be properly monitored. Users can easily sign up on large international platforms and usability tests are sometimes canceled to quickly reap the rewards. To prevent this, some platforms, such as User Sense, have built-in control mechanisms for this.

Get started with Usability Testing

The process of usability testing can be divided into four phases: making a usability test plan, conducting user tests, analyzing the results and making a usability test report. 

1 - Create a usability test plan

With the usability test plan you lay the foundation for the entire research, in which you record the entire process from start to finish. More information about drawing up a usability test plan can be found here: making a usability test plan.

2 - Perform user tests

In this step, the previously prepared test plan is implemented. Users are then invited to start using the usability test, and while doing so are filmed. If the test is attended by a moderator, you want to make sure that you let the users talk as much as possible.

3 - Analyzing the usability test results

In this phase all raw data has been collected and you can start forming an analysis. Depending on the amount of usability tests that are taken, it can be sometimes be difficult to keep an overview of the data that you have collected. Creating an affinity diagram is a suitable method to make large amounts of data manageable. 

4 - Making a usability test report

When you have collected and categorized all data you can summarize the results, identify issues in the design and make recommendations to address the issues.

After making adjustments to the website or app, it is advisable to test the product again. This way you find out if you have actually made progress.


Want to know more about user tests?

Download our whitepaper or example UX Research report.