System Usability Scale (SUS) Resources
by Tom Tullis
Originally posted August 16, 2018; Last updated Sept. 3, 2018
The System Usability Scale (SUS) is a ten-item rating scale for measuring
perceived usability. It was created by John Brooke while he was working at
Digital Equipment Corporation in 1986 in the U.K. Since then it has been
used been in over 1,200 published studies measuring the usability of things
as diverse as websites, mobile apps, desktop apps, various kinds of devices,
interactive voice response systems, and many more.
Here are the 10 statements used in SUS:
- I think that I would like to use this system frequently.
- I found the system unnecessarily complex.
- I thought the system was easy to use.
- I think that I would need the support of a technical person to be able
to use this system.
- I found the various functions in this system were well integrated.
- I thought there was too much inconsistency in this system.
- I would imagine that most people would learn to use this system very
- I found the system very cumbersome/awkward to use.
- I felt very confident using the system.
- I needed to learn a lot of things before I could get going with this
Respondents rate their level of agreement with each statement on a scale
from 1 ("Strongly Disagree") to 5 ("Strongly Agree"). Note that half the
statements are positively worded and half are negatively worded.
Here are some SUS resources that you might find useful:
And here are links to some other articles and studies about SUS:
- Measuring Usability with the
System Usability Scale (SUS) by Jeff Sauro
- 10 Things to Know
About the System Usability Scale (SUS) by Jeff Sauro
Usability Scale (SUS) overview on Usability.gov
Empirical Evaluation of the System Usability Scale by Aaron
Bangor, Philip Kortum, & James Miller
Factor Structure of the System Usability Scale by James R. Lewis
& Jeff Sauro
the Factor Structure of the System Usability Scale by James R.
Lewis & Jeff Sauro
- SUS: A
Retrospective by John Brooke
Benchmarks for the System Usability Scale by James R. Lewis &
Effect of Experience on System Usability Scale Ratings by Sam
McLellan, Andrew Muddimer, & S. Camille Peres
System Usability Scale and Non-Native English Speakers by Kraig
- When designing
usability questionnaires, does it hurt to be positive? by Jeff
Sauro and James R. Lewis
- Can I Leave This
One Out? The Effect of Dropping an Item From the SUS by James R.
Lewis & Jeff Sauro
Low Can You Go? Is the System Usability Scale Range Restricted? by
Philip Kortum & Claudia Ziegler Acemyan
What Individual SUS Scores Mean: Adding an Adjective Rating Scale
by Aaron Bangor, Philip Kortum, & James Miller
- Design and
Psychometric Evaluation of an American Sign Language Translation of
the System Usability Scale by Matt Huenerfauth, Kasmira Patel, and
the Utility of the System Usability Scale for Evaluating Voice-based
User Interfaces by Debjyoti Ghosh, Pin Sym Foong, Shan Zhang,
& Shengdong Zhao
Comparison of Questionnaires for Assessing Website Usability by
Thomas S. Tullis and Jacqueline N. Stetson