In an industry devoted to creating a great experience for people who use products, services, and apps, usability testing is paramount. The main goal of usability testing is to inform the design process from the perspective of the end-user.

UX researchers have developed many techniques over the years for testing and validating product hypothesis and particular design decisions. The methods range from well-known lab-based usability studies to those that have been more recently developed. In this article, we will explore seven different usability testing methods when you should use them and why.

Things to do before conducting usability testing

Before you pick a particular testing method, you should have a clear understanding of your target audience, available resources (time and money), and research objectives. This information not only will help you select the relevant testing method but also adjust the questions and tasks for your test participants.

Now let’s discuss usability testing methods that you might want to include in your test plan:

1. Guerilla testing

Guerilla testing is the simplest form of usability testing. Basically, guerrilla testing means going into a public place such as a coffee shop to ask people about your prototype. Test participants are chosen randomly.  They are asked to perform a quick usability test, often in exchange for a small gift (such as a free coffee). It’s low cost and relatively simple testing that enables real user feedback.

Man at cafe holding sign soliciting people to test his software
Man performing guerilla testing. Image by johnferrigan

When to use

Guerilla testing works best in the early stages of the product development process. When you have a tangible design (wireframes or lo-fi prototypes) and what to know whether you’re moving in the right direction or not.

Guerilla testing is also good for collecting personal opinions and emotional impressions about ideas and concepts.

It’s always important to understand that test participant in Guerilla testing might not represent your product’s target audience. That’s why Guerilla testing might not be right for testing niche products that require having special skills (i.e., software for finance brokers).

What to remember

The tasks you select for your testing session play a critical role in whether findings will be useful or not. Since it’s impossible to test everything at once, you need to prioritize all possible scenarios of interactions and select the most probable one (core user flow). It’s also important to remember that you will have a limited time per every test session. Usually, people who participate in guerilla testing will give you maximum 5-10 minutes of their time.

2. Lab usability testing

As the name suggests, lab usability testing is testing run in special environments (laboratories) and supervised by a moderator. A moderator is a professional who is looking to obtain feedback from live users. During a moderated test, moderators are facilitating test participants through tasks, answering their questions, and replying to their feedback in real-time.

When to use

Lab usability testing works best when you need to have in-depth information on how real users interact with your product and what issues they face. It will help you investigate the reasoning behind user behavior. The fact that this testing is moderated enables you to collect more qualitative information. At the same time, lab testing can be expensive to organize and run because you need to secure an environment, hire test participants, and a moderator. Another problem with this testing is the number of test participants in a single round. Usually, you have 5-10 participants per research round in a controlled environment. So it’s important to ensure that all test participants are reflective of your actual customer base.

What to remember

Lab usability testing requires having a trained moderator and a place for running a testing. Here are a few things to remember when choosing a moderator:

  • A moderator should always be ready to help test participants understand the purpose of testing (describe the goal) and keep the participant on track if they have any sort of confusion. However, it does not mean that a moderator should tell test participants what they should do.
  • Moderator should be good at decoding body language. Remember that what test participants say is not always the same as what they think. That’s why a moderator should be good at observing and analyzing body language and facial expressions.
  • The after-testing interview is an essential part of this type of testing. Moderators reach test participants after the testing session and ask them a few important questions.

With lab testing, there is always a risk that the controlled environment will be different from the user’s real environment. By placing the user in a controlled atmosphere, there is always a risk of creating a non-realistic user behavior.

3. Unmoderated remote usability testing

Unmoderated remote usability testing occurs remotely without a moderator. It offers quick, robust, and inexpensive user testing results to be used for further analysis. Test participants are asked to complete tasks in their own environment using their own devices and without a moderator present, which leads to the product being used naturally. The cost of unmoderated testing is lower; however, this type of testing offers less detailed testing results.

When to use

Unmoderated remote usability testing works the best when you need to obtain a large sample to prove critical findings from your initial moderated research. In other words, you have a particular hypothesis that you want to validate on a large segment of your users. Unmoderated remote usability testing will help you test a particular question or observe user behavior patterns.

What to remember

Remote usability testing doesn’t go deep into a test participant’s reasoning. That’s why it’s not recommended to use unmoderated remote testing as a first usability testing method.

4. Contextual inquiry

Contextual inquiry is less a usability testing method and more like an interview/observation method that helps a product team obtain information about the user experience from the real users. Test participants (real users) are first asked a set of questions about their experience with a product and then observed and questioned while they work in their own environments.

When to use

This technique is useful for getting rich information about users— their workspace, personal preferences, and habits. Getting all this information at the beginning of the design process will help the product team design a well-tailored experience. But this method also works for shipped products. It’s easy to prioritize the usability issues when you see them from the first-hand experience.

Contextual inquiry is also good when you want to test a user’s satisfaction with a product.

What to remember

Research should never provide their opinion during test sessions. The goal is to watch how test participants interact with a product, not participate in these interactions.

It’s important to take notes during the observation. Having notes after every observation session will help you write a detailed test report.

5. Phone interview

A phone interview is a remote usability test where a moderator verbally instructs participants to complete tasks on their device and feedback is collected automatically (the user interaction recorded remotely).

When to use

Phone interviews are an excellent way to collect feedback from test participants scattered around different parts of the globe.

What to remember

This type of testing requires a trained moderator. When it comes to interacting with test participants, a moderator should have excellent communication skills.

6. Card sorting

Card sorting is an excellent method for prioritizing content and features in user interface. The technique is relatively simple—all you need to do is place concepts (content, features) on cards and allow test participants to manipulate the cards into groups and categories. As soon as test participants sort the cards, a moderator should ask them to explain their logic (to understand the reasoning).

Sorted notecards hanging on a wall
Website card sorting on table. Image credit: Flickr

When to use

Card sorting is great when you want to optimize your product’s information architecture. By getting feedback on your navigation structure, you will be able to make more data-informed decisions.

What to remember

Card sorting will help you form a hypothesis on how to organize your content/features. But it’s always important to validate this hypothesis with real users. Sometimes changes that are supposed to improve the navigation experience lead to completely different outcomes.

7. Session recording

Session recording is a method of recording the actions that real (but anonymized) users take while they interact with a site. Session recording data helps to understand what content/features are the most interesting for the users (via heatmap analysis) as well as what interaction problems users face while they interact with your product.

When to use

Session recording will help you understand the major problems that users face when they interact with your product.

What to remember

To conduct a session recording, you need to use a special tool such as HotJar for that purpose.

Session recording works the best when it’s used together with another type of usability testing. By analyzing session recording results, you form a hypothesis on what problems users face, but you often need to conduct another testing to understand why they face this problem.

Why A/B Testing is not usability testing

Many UX specialists consider A/B testing as a usability testing method. It’s vital to understand that usability is all about having individuals experience a product’s functionality. And as we know, A/B testing is about experimenting with two or more versions of a page/screen to see which is most effective. The goal of A/B testing is to find the page that will convert better, while the purpose of usability testing is finding usability issues that prevent users from having great user experience.

A-B comparison. Split testing. Concept computer vector illustration
Cartoon A/B testing results. Image by Andrii Symonenko

Conclusion

With so many different usability testing methods, it’s often hard to select the one that will be good for your product. But don’t worry, every UX specialist faces the same problem. It’s essential to choose the method that you think will be good for your project and be flexible enough to change the direction if needed. Remember that the testing method you choose should be aligned with both your resources and your objectives.