The NASA-TLX is the most widely used workload measure in the human factors community, which provides a workload score form 0-100. It is a two-part survey in which the weighted average of 6 workload components (frustration, mental demand, effort, performance, temporal demand -i.e., time pressure, and physical demand) is calculated. In the first part, the users rate their experience of on a scale of 0-100 in 5 point increments. In the second part, the weights are calculated by having the users complete each possible paired comparison of the 6 workload components. That is, for each possible combination, the user indicates which contributed most to their experience of workload in the task. The NASA-TLX should be administered immediately after users complete a task before any debriefing occurs. Note, however, that users are instructed to focus on the last 90 minutes of the task.
Tools and resources related to the NASA-TLX can be found in the Planning Tools Section.
