Calorie Formula, Worked Example & Limitations

The resting equation

For weight W in kg, height H in cm and age A in years: resting kcal/day = 10W + 6.25H − 5A + s. The published binary sex coefficients are +5 for the male equation and −161 for the female equation.

Worked example

At age 35, 70 kg and 170 cm, the female equation gives 1,426.5 kcal/day. With activity 1.55, maintenance is 2,211.075, displayed as 2,211. The male equation gives 1,592.5 resting kcal/day. Display rounding does not change the calculation.

Units and accuracy

One pound is exactly 0.45359237 kg; one inch is exactly 2.54 cm; one kcal is 4.184 kJ. Unit changes preserve physical measurements internally to prevent repeated rounding drift. No formula can predict an exact personal requirement.

Who needs another approach

For adults 18–100 within the input limits. The source study involved 19–78, so other ages are extrapolations. Not for pregnancy, breastfeeding, children, eating-disorder care or medical nutrition treatment. Activity factors are assumptions separate from the published resting equation.

REE = 10 × kg + 6.25 × cm − 5 × age + s
s: male +5 / female −161
TDEE ≈ REE × activity
kJ = kcal × 4.184