Calculator
Basal metabolic rate (BMR) calculator
Your basal metabolic rate is the energy your body spends even if you never move: breathing, circulating blood, holding body temperature, repairing cells. For most people it is the single largest share of daily expenditure. The tool below works it out with theMifflin-St Jeor equation and also shows what happens to it at four activity levels.
Result
Basal metabolic rate
— kcal / day
Daily expenditure by activity level
BMR is not a target on its own. Your daily expenditure is BMR multiplied by an activity factor, and that number is called TDEE.
| Activity level | Multiplier | Daily expenditure |
|---|---|---|
| Sedentary (desk job, no exercise) | ×1.2 | — kcal |
| Lightly active (light exercise 1-3 days a week) | ×1.375 | — kcal |
| Moderately active (exercise 3-5 days a week) | ×1.55 | — kcal |
| Very active (exercise 6-7 days a week) | ×1.725 | — kcal |
The equation used
Mifflin-St Jeor (1990), the most widely used prediction equation in clinical practice today. The Cookrange app uses the same equation, so the result here matches what the app would tell you.
- Men: (10 × weight kg) + (6.25 × height cm) − (5 × age) + 5
- Women: (10 × weight kg) + (6.25 × height cm) − (5 × age) − 161
Worked example: for a 30-year-old man at 175 cm and 75 kg, (10 × 75) + (6.25 × 175) − (5 × 30) + 5 = 750 + 1,093.75 − 150 + 5 = 1,698.75 kcal. On a moderately active life (×1.55) daily expenditure comes to roughly 2,633 kcal.
The difference between BMR and TDEE
These are the two numbers people most often confuse. BMR is what you spend doing nothing. TDEE adds movement, exercise and digestion on top of it. The number used when setting a nutrition target is TDEE, not BMR - targeting BMR would mean eating as though you never got out of bed.
The definitions: basal metabolic rate,TDEE,maintenance calories,NEAT.
The limit of this estimate
Mifflin-St Jeor is a prediction equation, not a measurement. Your real basal expenditure can sit away from this figure: muscle mass, thyroid function, dieting history and genetics all affect it, and the equation knows none of them - only height, weight, age and sex. So treat the output as a starting point. Once a few weeks of real logged intake sit beside it, the estimate gives way to data. That handover is exactly what Cookrange'sprogress analytics does.
The other calculators
- Calorie and macro calculator — daily calorie requirement (TDEE) and a goal adjustment
- Macro calculator — splits calories into grams of carbohydrate, protein and fat
- Protein calculator — protein need per kilogram of bodyweight
- BMI calculator — body mass index and the healthy weight range
Sources
- Mifflin MD, St Jeor ST et al. (1990). A new predictive equation for resting energy expenditure in healthy individuals. American Journal of Clinical Nutrition, 51(2), 241-247.