In Brief
This study tested how accurately 18 step-based methods from research- and consumer-grade wearables measure real-world walking. Sixty adults aged 20–80 years wore six devices for seven days plus a waist-mounted video camera, which provided the criterion step counts. Only StepWatch met the ±10% equivalence margin for total steps with MAPE <10%. For total walking bout duration, only activPAL and ActiGraph wrist-StepCount met equivalence, and activPAL had MAPE <10%. No method accurately captured the number of walking bouts. Overall, activPAL, StepWatch, ActiGraph hip/1s, and ActiGraph wrist-StepCount performed best, but even these had limited accuracy for detailed walking patterns.