Once the answers are in
System Usability Scale calculator
Paste ten SUS ratings per respondent to calculate individual scores and the group mean. See the scoring formula and excluded rows. Everything runs in your browser.
No login required. Calculations run in your browser.
How this tool works
Use the standard ten-item System Usability Scale after a participant has used the system. Enter the original ratings from 1 (strongly disagree) to 5 (strongly agree), in item order. Do not reverse the inputs yourself.
For odd-numbered items, subtract 1 from the rating. For even-numbered items, subtract the rating from 5. Add the ten adjusted values and multiply by 2.5. A row alternating 4, 2 five times scores 75; a row alternating 5, 1 scores 100. Their mean is 87.5.
Only complete rows of ten integers from 1 to 5 are scored here. Malformed and out-of-range rows are excluded, not filled in. The score runs from 0 to 100 but is not a percentage. The group mean does not diagnose specific usability problems or establish a population benchmark.
Source: John Brooke, SUS: A quick and dirty usability scale (1996). In Plumeform, insert SUS from the scale library and preserve the item wording and order for automatic scoring.
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A useful next step
Use the scale library and keep the original item wording.
Connect your questionnaire to the task and audience.
A separate task-based questionnaire; it is not a SUS instrument.
Start
Put it into practice in your next survey.
100 responses a month on Free, and no credit card. Pro is $15 a month for 10,000 responses.