Basal Metabolic Rate Calculator
Find your basal metabolic rate with the revised Harris-Benedict equation from age, height, weight and sex, plus total daily needs for five activity levels.
Note: These calculations are for informational purposes only and do not replace professional tax or financial advice. All information without guarantee.
FAQ
Frequently Asked Questions
What is basal metabolic rate?
Basal metabolic rate (BMR) is the energy your body needs at rest for basic functions like breathing, circulation, and cell renewal. It accounts for about 60-75% of total daily energy expenditure.
How is basal metabolic rate calculated?
The most common formula is Harris-Benedict or Mifflin-St Jeor, using weight, height, age, and gender. Mifflin-St Jeor is considered more accurate for modern populations.
Does this calculator replace a doctor visit?
No. This calculator provides general orientation only. For medical questions, or before starting a diet, therapy or treatment, always consult a qualified physician or therapist.
Guide
What is the Basal Metabolic Rate Calculator?
The basal metabolic rate calculator computes the energy your body uses at complete rest, i.e. the minimum energy for organ functions.
How does the Basal Metabolic Rate Calculator work?
Enter sex, age, weight and height. The calculator computes the basal rate using the revised Harris-Benedict formula and shows the Mifflin-St Jeor value for comparison. The basal rate is the foundation for calculating total energy expenditure.
Key Data and Facts
Basal rate men: approx. 1,500-2,000 kcal/day. Women: approx. 1,200-1,600 kcal/day. The basal rate decreases with age and increases with muscle mass.
Step-by-Step Guide
How to calculate your basal metabolic rate (Grundumsatz) step by step: 1. State your sex: the formulas differ for men and women. 2. Enter your age, weight (kg) and height (cm). 3. Formula: the calculator uses the revised Harris-Benedict formula (Roza/Shizgal 1984): men: BMR = 88.362 + 13.397 x weight + 4.799 x height - 5.677 x age. Women: BMR = 447.593 + 9.247 x weight + 3.098 x height - 4.330 x age. For comparison it shows the Mifflin-St-Jeor value: men: BMR = 10 x weight + 6.25 x height - 5 x age + 5. Women: BMR = 10 x weight + 6.25 x height - 5 x age - 161. 4. Read off the result: the basal metabolic rate indicates how many calories your body burns at complete rest (organ functions, breathing, body temperature). 5. Calculate total energy requirement: multiply the basal metabolic rate by the PAL factor (Physical Activity Level): sedentary/little exercise 1.2, lightly active (exercise 1–3x a week) 1.375, moderately active (3–5x) 1.55, very active (6–7x) 1.725, extremely active (twice daily or physical work) 1.9. 6. For weight loss: reduce your calorie intake by 300-500 kcal below the total requirement. You should never go below your basal metabolic rate.
Calculation Example
Woman, 35 years, 65 kg, 168 cm: revised Harris-Benedict: BMR = 447.593 + 9.247 x 65 + 3.098 x 168 - 4.330 x 35 = 447.593 + 601.055 + 520.464 - 151.55 = 1,418 kcal/day. For comparison, Mifflin-St-Jeor: 10 x 65 + 6.25 x 168 - 5 x 35 - 161 = 650 + 1,050 - 175 - 161 = 1,364 kcal/day. Total requirement when lightly active (PAL 1.375): 1,418 x 1.375 = 1,949 kcal.
Sources
Official sources
Calculations are based on applicable German laws and official data:
Full methodology at Methodology.
Reviewed by Konstantin Iakovlev · Last updated:
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