📌 Overview

Calculate your Basal Metabolic Rate (BMR) using the Mifflin-St Jeor equation, plus your total daily energy expenditure (TDEE) based on activity level.

🔥 BMR Calculator

Calculate your Basal Metabolic Rate (BMR) using the Mifflin-St Jeor equation, plus your total daily energy expenditure (TDEE) based on activity level.

Gender

Age (years)

Height (cm)

Weight (kg)

Activity Level

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📋 How to Use

Enter your gender, age, height and weight.
Pick the activity level that matches your week.
Click Calculate to see BMR and TDEE.
Use TDEE as your maintenance calorie baseline.

❓ FAQ

What is the difference between BMR and TDEE?

BMR is what your body burns at complete rest, just keeping organs running. TDEE is BMR multiplied by an activity factor, representing everything you actually burn in a day.

Which formula does this use?

Mifflin-St Jeor, which research generally finds more accurate for most people than the older Harris-Benedict equation.

How accurate is it?

It is a population-based estimate, typically within about 10% for most adults. Body composition, genetics and medication can shift the real number.

❓ More Questions

What is the difference between BMR and TDEE?

BMR is the energy burned at complete rest to sustain basic life functions like heartbeat, breathing, and body temperature. TDEE is BMR multiplied by an activity factor and represents your actual total daily calorie burn.

How many calories should I eat to lose fat?

Usually a mild deficit of 300-500 kcal below TDEE works well; too large a deficit risks losing muscle and is hard to sustain. Adjust to your own situation or consult a dietitian.

💡 Use Cases

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Fat Loss Plan

Set a calorie target below your TDEE.

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Muscle Gain

Eat above TDEE for a controlled surplus.

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Maintenance

Match TDEE to hold your current weight.

🔗 Related Tools

📖 Deep Dive: BMR Calculator

What is basal metabolic rate

Basal metabolic rate (BMR) is the minimum energy your body uses to keep the heart beating, lungs breathing, body temperature steady, and organs running while you are fully awake, lying down, fasting, and in a comfortable environment. It usually makes up 60%-70% of daily energy use and is the baseline for any diet plan.

The formula

This tool uses the Mifflin-St Jeor equation: male BMR = 10 times weight(kg) + 6.25 times height(cm) - 5 times age + 5; female BMR = 10 times weight + 6.25 times height - 5 times age - 161. Compared with the older Harris-Benedict formula, it has smaller error in modern populations.

From BMR to TDEE

Multiply BMR by an activity factor to get total daily energy expenditure: sedentary 1.2, light 1.375, moderate 1.55, high 1.725, athlete 1.9. Example: a 30-year-old, 170cm, 65kg woman has a BMR around 1379 kcal; with light activity her TDEE is about 1896 kcal.

Things to keep in mind

Formulas are based on population statistics; individual variation can exceed 10%.

People with more muscle mass have a higher actual BMR than the estimate.

Long-term very-low-calorie diets lower metabolic adaptation and make the number unreliable.

Results are for reference only and do not replace professional nutrition or medical advice.