The reliability of commercially available pedometers is not known in detail. Therefore, the present study examines the accuracy and reliability of the FS500 (Acos), HJ301 (Omron), EX700 (Yamax), FB727 (Tanita) and TW600 (Citizen) pedometers to count steps and measure energy expenditure at various walking speeds. Twenty individuals (age, 32.5 ± 15.3 years; body mass index, 22.0 ± 1.6 kg/m2) walked at three speeds for 6 min. Step-counts and energy expenditure determined by each pedometer were compared with actual values. All five pedometers accurately measured steps at all speeds, but tended to underestimate expended calories to within 50% of the actual amount of energy expenditure. The correlation coefficients (R) between actual energy expenditure and pedometer values were between 0.74 and 0.87. Thus, feedback about energy expenditure is somewhat inaccurate. In contrast, step counts are very accurate, and thus pedometers are useful tools with which to indicate daily exercise levels.