Estimate resting energy expenditure with the Mifflin–St Jeor equation, then apply your selected activity factor to estimate total daily expenditure. Metric and imperial inputs are supported.
Resting kcal/day = 10 × kg + 6.25 × cm − 5 × age + s, with s = +5 for the male equation or −161 for the female equation. Daily estimate = resting estimate × activity factor.
For a 30-year-old using the male equation at 70 kg and 175 cm, resting expenditure is 1,648.75 kcal/day. A 1.2 activity factor gives about 1,979 kcal/day.
This adult estimate is not a measured metabolism test or a prescribed calorie intake. Activity factors are approximate; the ±10% display is an illustrative sensitivity band, not a statistical confidence interval. Pregnancy, illness, sport and individual physiology can require different assessment.
References support the identified formula, unit or jurisdiction. They do not imply endorsement of this site. Check the original document for current conditions and exceptions.
English edition: 16 September 2026.