BMR Calculator
Use this BMR calculator to calculate your basal metabolic rate, the calories your body burns at complete rest.
Calculated instantly in your browser — nothing is sent to or stored on our servers.
Alyssa Northrop, MPH, RD
Alyssa Northrop, MPH, RD, is a registered dietitian who earned her MPH in Human Nutrition at the University of Michigan and completed her dietetic internship there.
Medical Disclaimer: This calculator provides a general estimate based on established research and is for educational purposes only, not a substitute for medical advice. Individual results can vary based on health conditions, so consult a qualified healthcare professional or registered dietitian before making significant changes to your diet, exercise, or health routine. Read our full Medical Disclaimer.
How Basal Metabolic Rate (BMR) Is Calculated
Basal metabolic rate is the calorie floor beneath everything else you do in a day: the energy your body burns just to keep your heart beating, lungs breathing, and cells repairing themselves, before you’ve taken a single step. It’s the starting point this calculator estimates, and the same starting point the TDEE Calculator builds on once activity is added.
What BMR Measures
BMR isn’t a number you’d ever actually hit in real life, since simply getting out of bed pushes your calorie burn above it. It’s a reference floor used to build other estimates, most directly your TDEE.
The Formula
This calculator uses the Mifflin-St Jeor equation¹, which systematic reviews have identified as one of the more accurate predictive formulas for resting energy expenditure in healthy adults².
Men: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age in years) + 5
Women: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age in years) − 161
How This Calculator Computes Your Result
Enter your sex, age, height, and weight above. We run the Mifflin-St Jeor equation directly, no body fat percentage needed, and round to the nearest whole calorie.
Turning BMR Into a Full Daily Estimate
BMR alone doesn’t include any movement, exercise, or digestion. To find your total daily calorie burn, multiply your BMR by an activity factor, or use the TDEE Calculator to do that automatically.
A Note on Accuracy
Your total calorie needs depend on movement, exercise, digestion, and day-to-day variation that this number doesn't capture. For a more accurate picture, calculate your total daily energy expenditure, or TDEE.
Frequently Asked Questions
What does BMR actually measure?
BMR measures the number of calories your body burns at complete rest just to keep essential functions like breathing, circulation, and cell repair running.
Is BMR the same as the calories I should eat?
No. BMR doesn't include any daily movement or exercise. Multiply it by an activity factor to estimate your full daily calorie needs, known as TDEE.
Why does my BMR change with age?
Muscle mass tends to decline with age, and muscle burns more calories at rest than fat tissue, so BMR generally decreases gradually over the years.
Which formula does this calculator use?
This calculator uses the Mifflin-St Jeor equation¹, one of the more accurate predictive formulas for resting metabolic rate in healthy adults². If you want an estimate based on lean body mass instead, the TDEE Calculator switches to the Katch-McArdle formula when you provide a body fat percentage.
Sources
A New Predictive Equation for Resting Energy Expenditure in Healthy Individuals, Mifflin et al., 1990
Comparison of Predictive Equations for Resting Metabolic Rate in Healthy Nonobese and Obese Adults, Frankenfield et al., 2005
BMR Calculator
Use this BMR calculator to calculate your basal metabolic rate, the calories your body burns at complete rest.
Calculated instantly in your browser — nothing is sent to or stored on our servers.
Alyssa Northrop, MPH, RD
Alyssa Northrop, MPH, RD, is a registered dietitian who earned her MPH in Human Nutrition at the University of Michigan and completed her dietetic internship there.
Medical Disclaimer: This calculator provides a general estimate based on established research and is for educational purposes only, not a substitute for medical advice. Individual results can vary based on health conditions, so consult a qualified healthcare professional or registered dietitian before making significant changes to your diet, exercise, or health routine. Read our full Medical Disclaimer.
How Basal Metabolic Rate (BMR) Is Calculated
Basal metabolic rate is the calorie floor beneath everything else you do in a day: the energy your body burns just to keep your heart beating, lungs breathing, and cells repairing themselves, before you’ve taken a single step. It’s the starting point this calculator estimates, and the same starting point the TDEE Calculator builds on once activity is added.
What BMR Measures
BMR isn’t a number you’d ever actually hit in real life, since simply getting out of bed pushes your calorie burn above it. It’s a reference floor used to build other estimates, most directly your TDEE.
The Formula
This calculator uses the Mifflin-St Jeor equation¹, which systematic reviews have identified as one of the more accurate predictive formulas for resting energy expenditure in healthy adults².
Men: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age in years) + 5
Women: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age in years) − 161
How This Calculator Computes Your Result
Enter your sex, age, height, and weight above. We run the Mifflin-St Jeor equation directly, no body fat percentage needed, and round to the nearest whole calorie.
Turning BMR Into a Full Daily Estimate
BMR alone doesn’t include any movement, exercise, or digestion. To find your total daily calorie burn, multiply your BMR by an activity factor, or use the TDEE Calculator to do that automatically.
A Note on Accuracy
Your total calorie needs depend on movement, exercise, digestion, and day-to-day variation that this number doesn't capture. For a more accurate picture, calculate your total daily energy expenditure, or TDEE.
Frequently Asked Questions
What does BMR actually measure?
BMR measures the number of calories your body burns at complete rest just to keep essential functions like breathing, circulation, and cell repair running.
Is BMR the same as the calories I should eat?
No. BMR doesn't include any daily movement or exercise. Multiply it by an activity factor to estimate your full daily calorie needs, known as TDEE.
Why does my BMR change with age?
Muscle mass tends to decline with age, and muscle burns more calories at rest than fat tissue, so BMR generally decreases gradually over the years.
Which formula does this calculator use?
This calculator uses the Mifflin-St Jeor equation¹, one of the more accurate predictive formulas for resting metabolic rate in healthy adults². If you want an estimate based on lean body mass instead, the TDEE Calculator switches to the Katch-McArdle formula when you provide a body fat percentage.
Sources
A New Predictive Equation for Resting Energy Expenditure in Healthy Individuals, Mifflin et al., 1990
Comparison of Predictive Equations for Resting Metabolic Rate in Healthy Nonobese and Obese Adults, Frankenfield et al., 2005
BMR Calculator
Use this BMR calculator to calculate your basal metabolic rate, the calories your body burns at complete rest.
Calculated instantly in your browser — nothing is sent to or stored on our servers.
Alyssa Northrop, MPH, RD
Alyssa Northrop, MPH, RD, is a registered dietitian who earned her MPH in Human Nutrition at the University of Michigan and completed her dietetic internship there.
Medical Disclaimer: This calculator provides a general estimate based on established research and is for educational purposes only, not a substitute for medical advice. Individual results can vary based on health conditions, so consult a qualified healthcare professional or registered dietitian before making significant changes to your diet, exercise, or health routine. Read our full Medical Disclaimer.
How Basal Metabolic Rate (BMR) Is Calculated
Basal metabolic rate is the calorie floor beneath everything else you do in a day: the energy your body burns just to keep your heart beating, lungs breathing, and cells repairing themselves, before you’ve taken a single step. It’s the starting point this calculator estimates, and the same starting point the TDEE Calculator builds on once activity is added.
What BMR Measures
BMR isn’t a number you’d ever actually hit in real life, since simply getting out of bed pushes your calorie burn above it. It’s a reference floor used to build other estimates, most directly your TDEE.
The Formula
This calculator uses the Mifflin-St Jeor equation¹, which systematic reviews have identified as one of the more accurate predictive formulas for resting energy expenditure in healthy adults².
Men: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age in years) + 5
Women: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age in years) − 161
How This Calculator Computes Your Result
Enter your sex, age, height, and weight above. We run the Mifflin-St Jeor equation directly, no body fat percentage needed, and round to the nearest whole calorie.
Turning BMR Into a Full Daily Estimate
BMR alone doesn’t include any movement, exercise, or digestion. To find your total daily calorie burn, multiply your BMR by an activity factor, or use the TDEE Calculator to do that automatically.
A Note on Accuracy
Your total calorie needs depend on movement, exercise, digestion, and day-to-day variation that this number doesn't capture. For a more accurate picture, calculate your total daily energy expenditure, or TDEE.
Frequently Asked Questions
What does BMR actually measure?
BMR measures the number of calories your body burns at complete rest just to keep essential functions like breathing, circulation, and cell repair running.
Is BMR the same as the calories I should eat?
No. BMR doesn't include any daily movement or exercise. Multiply it by an activity factor to estimate your full daily calorie needs, known as TDEE.
Why does my BMR change with age?
Muscle mass tends to decline with age, and muscle burns more calories at rest than fat tissue, so BMR generally decreases gradually over the years.
Which formula does this calculator use?
This calculator uses the Mifflin-St Jeor equation¹, one of the more accurate predictive formulas for resting metabolic rate in healthy adults². If you want an estimate based on lean body mass instead, the TDEE Calculator switches to the Katch-McArdle formula when you provide a body fat percentage.
Sources
A New Predictive Equation for Resting Energy Expenditure in Healthy Individuals, Mifflin et al., 1990
Comparison of Predictive Equations for Resting Metabolic Rate in Healthy Nonobese and Obese Adults, Frankenfield et al., 2005