About this calculator
The Mifflin–St Jeor equation estimates BMR, the energy used at rest: 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5 for men, or − 161 instead of + 5 for women. Multiplying BMR by an activity factor estimates total daily energy expenditure.
Worked example
A 30-year-old man, 70 kg and 175 cm, has a BMR of about 1,649 kcal. With moderate exercise (×1.55), maintenance is about 2,556 kcal a day.
How to use the calorie calculator
- Choose the sex.
- Enter the age.
- Enter the weight.
- Enter the height.
- Read the result — it updates as you type.
Frequently asked questions
What is BMR?
Basal metabolic rate is the energy your body uses at complete rest to keep you alive.
How accurate is this?
It is a population-based estimate; real needs can differ by a few hundred calories.