Ballpark is the fastest way to capture high-quality feedback on questions, marketing copy, designs and prototypes using task driven questions.
The System Usability Scale (SUS) was the brainchild of John Brooke back in 1986. He created this “quick and dirty” tool to be able to measure the usability of a product or design. It has since been used to evaluate almost any kind of system including apps, hardware, mobile devices, software, and websites.
The survey consists of 10 statements, such as, “I found the product unnecessarily complex” and “I felt very confident using the product”. Respondents are expected to rate these statements on a scale of 1 to 5 based on how much they agree with which statement is presented to them. A score of 1 on the Likert Scale would indicate that the participant disagreed strongly and a score of 5 would mean they agreed completely. Each respondent’s total answers are then equated to a score between 1-100 - we’ll touch on this more later.
The System Usability Scale has been tried and tested for over 30 years, and has proven itself to be a dependable and valid method of evaluating the perceived usability of systems. So much so that it’s highly likely designers and researchers will still be counting on the System Usability Scale in many many years to come. Its ease and range of use as well as its versatility are also why it remains a popular usability test.
Incorporating the System Usability Scale should happen once you’ve developed your prototype and you’re ready to test.
You should include the 10 questionnaire type questions at the end of your Ballpark usability test to see how users interacted with your design or prototype and measure their experience.
As the system usability scale is a consistent tool, it can either be used across multiple tests allowing you to compare scores across designs, for example in A/B testing with two different designs, or yours against a competitors. Or it can be used to compare scores over time, for example monthly or quarterly.
The system usability scale:
System Usability Scale scores are not diagnostic. The results will not be able to diagnose any specific issues or provide context as to why each user responded the way they did but it does give you the green or red light about the usability of your design. Despite this subjective nature, it’s still a great tool for usability benchmarking, determining which aspects of the product or service need attention and improving, and seeing how you fare against your competitors.
Interpreting the system usability scale scoring can be a complex task. We mentioned before that each respondent rates a statement on a scale of 1 to 5 and that the total answers are then converted to a new score between 1 and 100.
The first thing to point out is that this conversion produces a percentile ranking - not to be confused with a percentage!
Each response is assigned a value for the System Usability Scale score calculation. The breakdown of points for the responses are:
And how do you convert the scores to a number between 1 and 100 you might ask? Here’s a simple step-by-step guide:
The average system usability scale score is 68. Simply put, a score of 68 will put the usability of your product or service in the 50th percentile.
Ballpark’s system usability scale template is designed so you can jump straight into testing your usability. This template includes all 10 of John Brooke’s questions which you can personalise and add your own context or explanation which will help the user take the test accurately.
Here’s a list of the questions included:
System usability scale FAQs