The Harris-Benedict Equation:

Males:  66 + (13.7 x W) + (5 x H) - (6.8 x A)                

 Females:  655 + (9.6 x W) + (1.7 x H) - (4.7 x A)

where:

W = actual weight in kg (weight in lb/2.2 lb/ kg)

 H = height in cm (height in inches x 2.54 cm/in)

 A = age in years

  Ex.  Joe weighs 150 lbs, stands 5'6", and is 21 years old

  150 lbs/2.2 lb/kg = 68 kg

  5'6" = 66 inches x 2.54 cm = 168 cm

  BMR = 66 + (13.7 x 68) + (5 x 168) - (6.8 x 21)

  BMR = 66 + 932 + 840 - 143 = 1695 kcals per day