What Is Usability? Designing for Ease

Imagine you’re a UX designer or UX researcher building a website. Can users easily find and browse product offerings despite never visiting the site before? Can they easily adjust items in their cart if they add something accidentally? Do customers leave the website feeling satisfied or confused and frustrated? These are some of the questions you’ll address by thinking about usability. Read on to learn more about what it is, why it's important for positive user experience, and how to measure it.

What is usability?

Usability is a way to measure how easy a product is to use. It is a concept in design circles to ensure products—whether websites, furniture, or hotel lobbies—can be used as simply and painlessly as possible. Jakob Nielsen, co-founder of leading user experience (UX) design firm Nielsen Norman Group and pioneer of usability, outlines five components that define good usability:

• Learnability: A user should be able to learn to carry out simple tasks the first time they use a product. 

• Efficiency: Users should be able to complete tasks quickly once they’ve grasped the basic design of the product.

• Memorability: Even if users don’t use a product for a period of time, they should be able to come back and remember how to use it.

• Errors: A user should make few severe errors, and a product should allow users to recover from them.

• Satisfaction: Using a product should be a pleasant experience.

Read more: What is UI Design? Definition, Tips, Best Practices

If usability is the ease of using something, utility is its actual usefulness. Utility asks of a product: Can you accomplish the task you set out to do in the first place? Even if an app to make haircutting appointments is easy to use and delightful to navigate (hallmarks of good usability), there’s no point in using it if you can’t actually make appointments. 

Usability and utility are, in turn, both distinct parts of the user experience (or UX). UX strategy encompasses the entire process of a user interacting with a product. Depending on the definition, UX can also include desirability, brand experience, credibility, accessibility, and findability.

What are the usability heuristics?

In addition to the five components of usability, Jakob Nielsen defined the 10 usability heuristics. The usability heuristics are considered rules of thumb for designers who want to create intuitive products. The 10 heuristics of usability are as follows:

1. Visibility of system status 2. Match between the system and the real world 3. User control and freedom 4. Consistency and standards 5. Error prevention 6. Recognition rather than recall 7. Flexibility and efficiency of use 8. Aesthetic and minimalist design 9. Help users recover from errors 10. Help and documentation

Why does usability matter?

Good usability means users can accomplish their tasks quickly, with minimal stress and errors, and ultimately feel satisfied when interacting with a product's user interface. For companies creating products, this user-centered design becomes important for both attracting customers and retaining them through user satisfaction. Customers are more likely to gravitate toward products with better usability and more likely to recommend those products to other people.

For websites, usability is particularly crucial. Think about how easily users can leave when they encounter difficulty or confusion. When you buy a physical product, you must go to the store or post office to return it. With a website, it’s much easier to navigate away from a less-than-ideal product.

What is usability testing?

Designers, user researchers, and usability specialists often run products through a process called usability testing, which can help determine what expectations, preferences, and troubles a user has. Once they have conducted a usability study, obtained user feedback, or observed user behavior, they can gain a clearer idea of what's going well—and what isn't—to refine a design until it meets user expectations.

Read more: What is Usability Testing?

What is a usability test? With examples

Usability tests are important to conduct throughout the design process so that you can identify potential issues as early as possible. Usability testing takes several different forms, depending on which component is being measured. The next section outlines a few examples of usability tests:

• Card sorting: Write out concepts (like features) on notecards, and ask participants to organize them into groups that make sense, then create labels for those groups. Card sorting is useful in organizing a website or mobile app and is often used in the mockup or wireframing stage.

• Guerilla testing: A team brings a design or prototype into a public space like a cafe or park, and passersby are asked for their input. This can be a quick, low-cost way to gather feedback.

• Session recordings: Often used with digital products like websites or apps, session recordings entail a researcher watching a user's recorded session navigating the product to accomplish a task. This can also include a heatmap analysis—a visual representation of where most users click, scroll to, or point their mouse.

• Lab usability testing: Participants are invited into a controlled environment where a moderator can observe their behavior or ask questions as they interact with a product. Since lab tests require significant coordination, and participant numbers are usually limited to small groups, lab testing is good for in-depth, qualitative research.

• Remote usability testing: Participants complete a series of tasks at home. Remote usability testing can be monitored or unmonitored: If it's monitored, a user researcher is likely "watching" the participant use the product in real-time via a shared virtual space, whereas if it's unmonitored, the participant will record their session for a researcher to review later.

Determining which is the best usability test for your product depends on your budget, scheduling, and time constraints. Remote usability testing tends to be less expensive than in-person testing, but in-person testing can reveal a wealth of helpful information thanks to a user's body language, facial expressions, and more.

Read more: What is a UX Researcher? How to Get the Job

How do you measure usability?

Usability tests will ideally reveal a lot about how your product can be improved. If you’re keeping an eye out for metrics on how to improve usability, consider the following metrics: 

• Success rate: Whether users can complete a task at all

• Time: How long it takes for users to complete a task

• Error rate: How many errors users made

• Satisfaction: How satisfied users were

Read more: What Is a User Story? Understanding Its Role in Agile Development and UX

Tip: Before you begin designing a new product or redesigning an older product, it's important to conduct pre-design research. Spend time researching and defining 1) who your users are, 2) what the central design problem is, and 3) what the design requirements are.

Who can benefit from learning about usability?

Usability is a useful concept for almost any type of marketer, developer, designer, or user researcher. Examples include UX designers, product designers, UX researchers, visual designers, and web developers. Usability can also be exceedingly helpful for product managers, UX engineers, UX writers, and anyone involved in creating a product.

Learn to leverage usability in your design practice on Coursera

Implementing usability principles into a creation process can make a product easier, more intuitive, and more satisfactory to use.

Master usability testing and other key concepts of UX design in as little as two months with the University of Michigan's online specialization, User Experience Research and Design Specialization. You'll learn to conduct user research and write reports to guide the product design process. By the end, you'll earn a sharable certificate for your resume.

Looking to earn a certificate to demonstrate your new skill set? In the Google UX Design Professional Certificate program, you’ll learn the basics of UX research and testing and plan your own UX research study. Upon completion, you'll earn a professional certificate from an industry leader in technology.

If you're looking to practice and prove the skills you already have, you might benefit from a Guided Project that focuses on creating something for your portfolio. For example, the iPhone Application Flow with Wireframes in Miro project focuses on applying UX principles and designing an iPhone app flow.