The NASA TLX app, developed by NASA, is the official Task Load Index widely used for measuring subjective workload in various industries. It facilitates workload assessments on operators dealing with human-machine interface systems. By utilizing a multi-dimensional rating procedure, the app calculates an overall workload score based on six sub scales: Mental Demand, Physical Demand, Temporal Demand, Performance, Effort, and Frustration.

Originally a paper questionnaire from NASA Ames Research Center, the NASA TLX sets the standard for workload measurement. The app enhances accessibility, allowing for mobile assessments in diverse environments like aircraft cockpits and control workstations. Key features include ensuring participant data privacy, location flexibility without network dependency, and a streamlined study setup via QR code scanning.