Web usability testing: Building websites that work for real users

UserWay

Web usability testing: Building websites that work for real users

Table of contents

Website usability testing is a structured process where real users complete specific tasks on a website while a researcher reviews where they succeed, hesitate, or struggle. Usability testing with people with disabilities can surface valuable insight on web accessibility.

More than 1.3 billion people worldwide live with some form of disability. For each of them, a website that’s hard to navigate isn’t a minor annoyance—it’s a wall. So how can you find those walls and tear them down before they cost you customers, conformance, or credibility? Web usability testing with people with disabilities is a key part of the process.

At its core, web usability testing is simple: real users try to complete specific tasks on your site while a researcher tracks where they breeze through, where they stall, and where they give up. In usability testing that’s specifically focused on accessibility, these users are people with disabilities.

In this guide, we’ll take a deeper dive into website usability testing, covering both standard methods and practices specific to accessibility.

Key insights

An estimated 1.3 billion people live with a significant disability, so accessible design isn’t a niche concern—it reaches a huge audience and backs up your legal obligations across major markets.
Automated scanning tools are fast and genuinely useful for identifying common accessibility issues, but they can’t replace testing with real people, including those who use assistive technology.
In the context of accessibility, website usability testing is the practice of engaging users with disabilities to navigate a site using assistive technology and share barriers and challenges they encounter.
Moderated testing tells you why users struggle; unmoderated testing tells you how often, at scale.
Poor usability for people with disabilities can cost you customers. Confusing navigation is one of the top reasons people leave a site without doing what they came to do.

What is website usability testing?

Website usability testing puts representative users in front of your website and asks them to complete specific tasks while a researcher records where they succeed, hesitate, or struggle. The point is to catch problems before they reach your whole audience.

In a typical usability testing session, you’ll track task completion rate, time on task, error rate, and user satisfaction. Those metrics turn fuzzy impressions of user behavior into numbers you can act on. The Nielsen Norman Group found that testing with just five users surfaces around 80% of usability problems, so a handful of small, regular rounds of user testing will teach you far more than one big study ever will. That makes lightweight user testing one of the highest-return habits a web team can build.

The stakes are practical: a clunky user experience drives people away, while a smooth website user experience earns trust and brings them back.

Website usability testing and accessibility

Usability testing is part of the wider world of user research, and standard practices may or may not cover accessibility. However, conducting usability testing with people with disabilities is a best practice for ensuring website accessibility.

To understand the distinction between testing for general usability, and usability testing for web accessibility, it’s helpful to briefly define these two terms:

Web usability refers to how easy and intuitive a website is to use
Web accessibility refers specifically to how usable a website is for people with disabilities.

Conducting usability testing for accessibility can help you answer important questions like:

Can someone navigate the whole site with a keyboard instead of a mouse?
Are forms labeled clearly enough so that users can complete them intuitively?
Is alt text meaningful for screen reader users?

This adds a valuable layer of insight that goes above and beyond what other forms of accessibility testing can provide. For example, automated tools like UserWay’s Accessibility Monitor scan your code and flag issues such as missing alt text, color contrast failures, and unlabeled form fields—but they can’t detect all issues.

Manual audits provide more comprehensive and reliable insight than automated testing, but they tend to focus on baseline conformance with standards like the Web Content Accessibility Guidelines (WCAG). This is critical for compliance, but doesn’t provide the same insight into the quality of an actual user’s experience that you get from observing real people work through real tasks.

By engaging users with a wide range of needs and understanding their challenges, you can not only meet legal and ethical standards, but ultimately provide an experience that’s genuinely enjoyable for everyone.

What are the main website usability testing methods?

Both general and accessibility-focused usability testing is usually conducted in one of three ways:

Moderated in-person usability testing: Participants perform tasks on your website in a controlled environment, like a lab, while a moderator reviews their actions and asks follow-up questions. In-person testing is great for probing deeper into a participant’s behavior and gathering user feedback in real time. It is the most established method for high-stakes decisions.
Remote moderated tests: One of the most flexible moderated tests, conducted remotely by video call. Useful for reaching users in different locations and observing them in their own environment.
Unmoderated testing: Participants complete test scenarios at their own pace through a platform that records their interactions. Because each participant completes tasks independently, this testing method scales quickly and works well for gathering quantitative data from a wide user base.

Other types of web usability testing include:

Tree testing: Often a follow-up to card sorting, this tests how easy it is to find information within a website’s structure. Participants locate topics starting from the main menu, which reveals how well the website architecture works.
A/B testing: A form of quantitative usability testing where two versions of a web page are served to similar groups at the same time. The one that performs better, typically measured by conversion rates, task completion, or engagement, is kept.
Eye tracking: Tracks where and how long a user focuses on different parts of a webpage. Valuable for understanding what draws attention and whether users are focusing on the right elements.
Session recordings and heatmaps: These tools capture video recordings of real user sessions, showing how visitors interact with your website. Reviewing recordings surfaces pain points across your site that other methods miss.
Cognitive walkthrough: Evaluators work through specific user interfaces as a representative user would, finding points where the interface is likely to cause confusion. Quick to set up and useful in early design stages.
First-click testing: Participants review a page and indicate where they would first click to complete a given task. First-click accuracy is a strong predictor of overall task success.

What makes web usability testing effective?

The best web usability testing pulls from two angles at once.

Qualitative usability testing methods like moderated sessions and think-aloud testing get at the why: the assumptions people bring, the logic they follow, and the exact moment they throw up their hands.
Quantitative usability testing—A/B studies, task completion rates, error counts—tells you how often and how badly those problems bite. Use them together and you get the full shape of your site’s user experience, plus a clear path to a better customer experience.

Remote testing is worth a special mention. Letting people test from wherever they actually are—home, the office, a phone on the train—tends to produce more honest user feedback than a sterile lab. People behave differently on home turf, and the way someone tackles everyday tasks in real life is often very different from how they’d handle the same tasks under observation. That gap is exactly what shapes the real user experience.

Usability testing vs. functional testing: What’s the difference?

It also helps to know how website usability relates to functional testing, because the two are frequently confused.

Functional testing checks that the machinery works: links go where they should, forms submit, features do what they promise. Skip it and you’ve built a car with no engine. Like usability testing, functional testing can also be performed specifically for accessibility. This process typically involves an expert completing specific tasks on a website with assistive technology and documenting what’s broken.

Usability testing asks a different question entirely—the human one. Usability refers to whether people can navigate your website, find what they need, and complete tasks without friction. Do they complete tasks quickly and confidently, or do they wander off and quit?

It’s about intuitiveness and whether the website lives up to what customers expect. And it hits the bottom line directly: confusing navigation and broken task flows are among the most common reasons people abandon a website before finishing a purchase or sign-up, which drags conversion rates down with them.

How should a usability testing process work?

Here’s how the test process for website usability testing usually goes in practice, whether you’re running moderated sessions or unmoderated tests. The goal at every step is the same: learn whether real people can complete the tasks that matter.

Set your testing objectives. Decide which parts of website usability you’re testing. If you’re testing for accessibility, this may include screen reader compatibility, keyboard navigation, and color contrast. You also need to define what a win looks like. “Can users actually complete this task?” is a solid place to start.
Recruit participants. Pull from your target audience. Even if you’re testing usability broadly, rather than accessibility specifically, it’s a best practice to make sure people with disabilities are in the mix.
Run a pilot test. Before the real sessions, do a dry run with one participant. Whether you’re doing in-person testing or running things remotely, a pilot is the cheapest way to catch broken test scenarios, fuzzy instructions, and timing problems before they corrupt your main data.
Conduct the test. Observe how each participant works through the tasks you’ve set on your website. Encourage the think-aloud method—having them narrate their thinking as they go—so you get a direct line into their behavior in real time. Note which tasks they complete easily and where they hit a wall.
Gather feedback and analyze results. After each testing session, ask about the overall experience and any pain points. That feedback helps you tell a genuine usability problem from a one-off fluke. Follow-up questions are great for unpacking hesitations you noticed mid-session. Then dig into task completion rates, time on task, and abandonment rates alongside your raw data, and sort what you find into critical, moderate, and low-priority usability issues.
Act and retest. Redesign the rough spots, tighten up navigation, or improve compatibility with assistive technology. Catch things early in the development process and they’re cheap to fix. Then test again after your changes land, and keep performing usability testing at different stages of your site’s life—not just once.

Tips to conduct usability testing for your own website

If you’re ready to start testing the usability of your site, the following tips can help you get started:

Recruit the right people. Three to five participants from your existing users or target audience is the sweet spot. They don’t need to be experts—they just need to represent the people who actually use your site.
Set clear objectives. Work out what you want to learn before anyone sits down. Frame realistic tasks around what real visitors come to do on your website, and resist the urge to hand them step-by-step instructions. A good task sounds like this: “You’ve just learned about this company and want to find out whether they deliver to your area.”
Run a pilot test first. Try your setup on one person before the main sessions. You’ll catch the confusing instructions and technical hiccups before they wreck your results.
Use the think-aloud method. Ask participants to say what they’re thinking as they go. It turns silent clicking into observable data you can do something with.
Prioritize what you find. Sort findings into critical, moderate, and low-priority buckets, and fix the blockers first.
Test early and often. Small, frequent tests catch problems while they’re still cheap to fix. Wait for one big audit and you’ll be fixing everything at once, under pressure.

When it comes to usability testing for accessibility, it can be helpful to get support from an expert. The partnership between Level Access (UserWay’s parent company) and Fable offers real-world testing by people with disabilities, so you can validate that your site works for assistive technology users.

Start improving accessibility and user experience with UserWay

Truly usable websites work for everyone—whether they navigate with a mouse or use screen readers, keyboard-only navigation, magnification, or voice control. And when you design for a broad range of access needs, you don’t just provide a better experience for people with disabilities. You elevate the experience for everyone.

Getting started with web accessibility doesn’t need to be complicated. UserWay provides accessibility solutions that work for you, no matter where you are on your accessibility journey. From fast-start automation to expert-led audits, we’re ready to help you meet your accessibility goals.

Frequently asked questions

Why is usability testing important?

Because it surfaces the barriers that stop people from finishing tasks—the kind internal teams rarely catch on their own. Better website usability feeds straight into customer satisfaction, conversion rates, and regulatory compliance.

Who should perform usability testing?

Plenty of people can conduct usability testing: UX designers, a product team, a design team, in-house researchers, or specialist agencies. But you don’t need any of them to get started—website owners can run effective usability testing themselves. The self-testing section above is a good starting point.

When should usability testing be conducted?

Ideally, all the way through the development process, from early design to well past launch. Testing early catches problems while they’re still cheap to fix, and repeating tests at different stages produces a stronger product. Whenever you ship a new feature, run a quick check that people can still complete the key tasks they rely on.

How often should you test a website for usability?

Every quarter is a reasonable rhythm, plus a round after any significant update. Small, frequent tests with three to five users do more for overall usability than the occasional big study.

How many users do I need for usability testing?

For qualitative usability testing, five users per audience segment usually does the job. If your audience spans a wide range of ages, abilities, or devices, bump that to eight to ten per segment for more reliable coverage. For quantitative usability testing, where you need statistically solid metrics, many researchers suggest aiming for around 40 users.