System Usability Scale

<p>The System Usability Scale (SUS) is a reliable tool used to evaluate the usability of a wide range of products and services. Originally developed by John Brooke in 1986, SUS helps in assessing how user-friendly a system is by providing a quick and simple way to collect user feedback. Each participant rates ten statements about the system on a five-point Likert scale, ranging from "Strongly Disagree" to "Strongly Agree". The resulting scores are then converted into a single usability score ranging from 0 to 100.</p> <p>Given its simplicity and effectiveness, SUS is widely used across various industries, including software development, web design, and hardware manufacturing, to ensure that products meet user expectations and are easy to use. Its versatility makes it an indispensable tool in the arsenal of UX designers and researchers.</p> <h2>Components of the System Usability Scale</h2> <p>The SUS questionnaire consists of ten statements that cover various aspects of usability, including ease of use, complexity, and user's confidence in using the system. Here are the ten statements:</p> <ul> <li>I think that I would like to use this system frequently.</li> <li>I found the system unnecessarily complex.</li> <li>I thought the system was easy to use.</li> <li>I think that I would need the support of a technical person to be able to use this system.</li> <li>I found the various functions in this system were well integrated.</li> <li>I thought there was too much inconsistency in this system.</li> <li>I would imagine that most people would learn to use this system very quickly.</li> <li>I found the system very cumbersome to use.</li> <li>I felt very confident using the system.</li> <li>I needed to learn a lot of things before I could get going with this system.</li> </ul> <h3>Calculating the SUS Score</h3> <p>To calculate the SUS score, each item’s score contribution ranges from 0 to 4. For items 1, 3, 5, 7, and 9, the score contribution is the scale position minus 1. For items 2, 4, 6, 8, and 10, it is 5 minus the scale position. The scores are then summed up and multiplied by 2.5 to convert the total score to a scale from 0 to 100.</p> <h2>Benefits of Using SUS</h2> <p>SUS offers several benefits that make it a preferred choice for usability testing:</p> <ul> <li>**Simplicity**: The SUS questionnaire is straightforward and easy to administer, making it accessible for both users and researchers.</li> <li>**Versatility**: SUS can be used for a variety of products, including websites, mobile apps, and physical devices.</li> <li>**Benchmarking**: SUS provides a quantitative measure that allows for easy comparison across different systems and iterations.</li> <li>**Reliability**: Numerous studies have validated the reliability and effectiveness of SUS in assessing usability.</li> </ul> <h2>Challenges and Considerations</h2> <p>Despite its widespread use, there are some challenges and considerations when using SUS:</p> <ul> <li>**Cultural Differences**: Users from different cultural backgrounds may interpret and respond to the SUS statements differently, potentially affecting the results.</li> <li>**Context of Use**: The context in which the system is used can influence the responses. It's essential to consider the specific use case when interpreting the results.</li> <li>**Score Interpretation**: While the SUS score provides a quantitative measure of usability, it doesn't pinpoint specific usability issues. Qualitative feedback should be gathered alongside SUS to gain a comprehensive understanding of user experience.</li> </ul> <h2>Real-World Examples</h2> <p>Many companies have successfully used SUS to enhance their product usability. For instance, <a href="https://www.nngroup.com/articles/usability-metrics" style="color:#2896FF; text-decoration: underline;">NNG</a> used SUS to evaluate various digital products, leading to significant improvements in user satisfaction and performance. Similarly, climate tech companies like <a href="https://www.climacell.co" style="color:#2896FF; text-decoration: underline;">Climacell</a> have utilized SUS to ensure their weather intelligence platforms are user-friendly for diverse user groups, including farmers and city planners.</p> <h2>Conclusion</h2> <p>The System Usability Scale is a powerful tool for assessing and improving the usability of products across various industries. By providing a quick and reliable measure of user satisfaction, SUS helps organizations identify usability issues and make informed decisions to enhance the user experience. For more information on improving your product’s usability, consider exploring additional resources and conducting comprehensive UX audits.</p> <p>To understand the power of design across industries and sectors, view our diverse portfolio of works. <a href="https://www.whatifdesign.co/work" style="color:#2896FF; text-decoration:underline;">View our portfolio</a>.</p> <p>Increase user engagement that converts your demos into sales. Optimise your UX strategies with our audits. <p>Fill out the <a href="https://tally.so/r/n97pxQ" style="color:#2896FF; text-decoration:underline;">UX Audit form</a> to get started. Ready to discuss your needs? <a href="https://cal.com/akhilak/what-if-design?duration=25" style="color:#2896FF; text-decoration:underline;">Book a consultation call</a> with us today.</p></p>