2,555.56 cal/day
Mifflin-St Jeor
BMR, or basal metabolic rate, is the energy your body needs at rest to support vital functions. These include breathing, circulation, cell work, and body temperature control. It excludes exercise and movement.
A calorie measures energy. Your body gets calories from food and uses that energy for basic functions, movement, digestion, exercise, and other daily activity. One calorie on food labels means one kilocalorie.
Our BMR Calculator quickly estimates your daily calorie needs from your personal details. Enter simple measurements, choose your profile, and get a clear BMR result to guide calorie planning and study.
Enter your weight, height, and age.
Choose your gender and activity level.
Get your BMR and daily calorie needs instantly.
Copy the calculated calorie details for future use.
Enter your weight, height, and age.
Choose your gender and activity level.
Get your BMR and daily calorie needs instantly.
Copy the calculated calorie details for future use.
Use a proven equation and consistent units to estimate resting energy needs. This gives a useful starting estimate.
Men: Women:
A 25 year old man weighs 70 kg and is 175 cm tall. His estimated BMR is about .
Our calculator uses BMR equations to estimate resting energy needs. Each formula uses different inputs, so results may vary slightly.
The Mifflin St Jeor equation uses age, sex, weight, and height. It gives a practical BMR estimate for many adults and works well as a general starting point when direct testing is not available.
Mifflin St Jeor:
for men.
for women.
The Revised Harris Benedict equation estimates BMR from age, sex, weight, and height. It is an older formula, but it remains useful for comparison, study, and understanding how predictive equations differ.
Revised Harris Benedict:
Men: .
Women: .
The Katch McArdle formula uses lean body mass instead of sex as a main input. It can help when body composition data gives a reliable lean mass value for the person being assessed.
Katch McArdle: .
No BMR formula is perfectly accurate for every person. Mifflin St Jeor works well for many adults, while formulas using lean body mass may help in selected cases. Indirect calorimetry gives a direct measurement.
BMR depends on body size, age, sex, lean mass, genetics, hormones, and pregnancy. These factors can change resting energy needs.
Age affects BMR because energy needs often change as the body ages. BMR may fall with age, especially when muscle mass decreases. This makes age a key input.
Body weight affects BMR because a larger body usually needs more energy to support basic functions at rest. Weight loss can also lower resting energy needs.
Height can affect BMR because a larger body often has more tissue that needs energy to function. Height also appears in several BMR equations.
Sex is used in common BMR equations because average body composition and energy needs can differ between males and females.
Lean body mass strongly affects BMR because muscle and other lean tissues use energy even when you rest. More lean mass can raise resting needs.
Genetics can affect metabolic rate. People with similar age, height, and weight may still have different resting energy needs because biology varies between people.
Hormonal factors can change metabolic rate. Thyroid hormones, for example, help regulate how quickly the body uses energy at rest.
Pregnancy changes energy needs as the body supports fetal growth and other changes. Standard BMR estimates may not fit every pregnancy.
You can support a healthy metabolic rate by building muscle, eating enough nutritious food, staying active, sleeping well, and avoiding extreme calorie restriction. These habits support healthy energy balance, steady daily energy use, better fitness, and sustainable weight management.
You can support BMR with muscle, nutrition, activity, sleep, and healthy calorie intake. Results vary because many factors affect metabolic rate.
Building or maintaining muscle can support resting energy needs because lean tissue uses energy. Strength training can help preserve muscle during weight management.
Adequate nutrition gives your body energy and nutrients for normal functions. A balanced diet can help protect lean body mass during calorie control.
Regular physical activity supports fitness and energy balance. Exercise can affect body composition and total calorie needs, while BMR varies.
Adequate sleep supports normal body functions and healthy energy regulation. Poor sleep can affect appetite, activity, and weight management.
Extreme calorie restriction can reduce energy use as the body adapts. Avoid very low calorie plans unless a qualified professional recommends them.
Important Note for BMR Tests
A BMR calculator gives an estimate, not a direct medical measurement. Predictive equations cannot capture every individual difference. Clinical testing, such as indirect calorimetry, can measure resting energy use more directly when a precise assessment is needed.
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These BMR Calculator FAQs explain BMR, calorie needs, health meaning, changes, diet, TDEE, RMR, and daily use.