BMR Calculator
Calories your body burns at rest
Your BMR
Daily calories by activity level
| Activity | Calories a day |
|---|---|
| Sedentary: little or no exercise | 1,941 kcal |
| Light: exercise 1–3 days a week | 2,224 kcal |
| Moderate: exercise 3–5 days a week | 2,507 kcal |
| Active: exercise 6–7 days a week | 2,790 kcal |
| Very active: hard exercise or a physical job | 3,073 kcal |
- 1Enter your detailsSex, age, weight and height
- 2Pick a formulaMifflin–St Jeor is the default
- 3See your BMRPlus calories for each activity level
BMR formulas
BMR is the energy your body needs just to stay alive at rest: breathing, circulation, keeping warm. With W in kg, H in cm and A in years:
Mifflin–St Jeor: 10W + 6.25H − 5A + 5 (men) or − 161 (women)
Harris–Benedict (men): 88.36 + 13.40W + 4.80H − 5.68A
Katch–McArdle: 370 + 21.6 × lean body mass (kg)
BMR vs TDEE
BMR is only your resting burn, usually 60–70% of the calories you use in a day. Your total daily energy expenditure (TDEE) adds digestion and movement: multiply BMR by your activity factor, as in the table.
Which formula to use
Mifflin–St Jeor is the most accurate for most people and is recommended by dietitians. Katch–McArdle can be better for lean, muscular people if you know your body fat percentage.
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Frequently asked questions
What is a normal BMR?
Roughly 1,200–1,500 kcal a day for women and 1,500–1,900 kcal for men, depending on size and age.
Should I eat less than my BMR to lose weight?
It's not recommended. Eat below your TDEE (BMR × activity) but generally not below your BMR, so your body gets enough energy for basic functions.
Why does BMR drop with age?
We tend to lose muscle as we age, and muscle burns more energy than fat. Strength training helps keep BMR up.
Sources
- Mifflin MD et al. A new predictive equation for resting energy expenditure. Am J Clin Nutr, 1990
- Roza AM, Shizgal HM. The Harris Benedict equation reevaluated. Am J Clin Nutr, 1984
Last reviewed: October 2026