Metabolism Calculator
Calculate your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE) using the Mifflin-St Jeor formula.
BMR
1,618 kcal/day
Calories your body needs at complete rest
TDEE
2,507 kcal/day
Calories needed to maintain current weight
Estimated Daily Calories for Weight Goals
Lose Weight
2,007
kcal/day ( −500 )
Maintain
2,507
kcal/day
Gain Weight
3,007
kcal/day ( +500 )
Gender
Activity Level
Calculate your BMI
Check your Body Mass Index and WHO classification →
BMR and TDEE are estimates based on population averages. Individual metabolism varies based on genetics, body composition, and other factors. All calculations run locally in your browser — your data is never sent to any server.
Understanding your metabolism is the foundation of effective weight management and fitness planning. Our Metabolism Calculator uses the evidence-based Mifflin-St Jeor equation to compute your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE). Whether you want to lose weight, maintain, or build muscle, knowing your daily calorie needs helps you set realistic targets. All calculations run instantly in your browser — no data leaves your device.
What Is BMR?
Basal Metabolic Rate (BMR) is the number of calories your body needs to perform essential life-sustaining functions at complete rest — breathing, circulation, cell production, and temperature regulation. It accounts for 60–75% of your total daily calorie burn. Our calculator uses the Mifflin-St Jeor formula, which is widely regarded as the most accurate for the general population:
- Male:
BMR = 10W + 6.25H − 5A + 5 - Female:
BMR = 10W + 6.25H − 5A − 161
W = weight in kg, H = height in cm, A = age in years
What Is TDEE?
Total Daily Energy Expenditure (TDEE) estimates the total calories you burn in a day, including physical activity. It is calculated by multiplying your BMR by an activity factor based on your lifestyle. TDEE is the true number to use when setting calorie targets for weight loss, maintenance, or muscle gain.
How to Use the Metabolism Calculator
- Select your gender — Male or female, which adjusts the BMR formula.
- Enter your age — Type your current age in years.
- Enter your weight and height — Provide your body weight in kilograms and height in centimeters.
- Choose your activity level — Select the option that best matches your typical weekly physical activity.
- Read your results — Your BMR, TDEE, and estimated calorie targets for weight goals update instantly.
Activity Levels Explained
- Sedentary (×1.2): Little or no exercise, desk job
- Lightly Active (×1.375): Light exercise or sports 1–3 days per week
- Moderately Active (×1.55): Moderate exercise or sports 3–5 days per week
- Very Active (×1.725): Hard exercise or sports 6–7 days per week
- Extremely Active (×1.9): Very hard daily exercise, physical job, or training twice a day
Key Features
- Mifflin-St Jeor Formula
Evidence-based BMR calculation used by health professionals.
- Real-Time Results
BMR, TDEE, and weight goal calories update instantly.
- 5 Activity Levels
From sedentary to extremely active — find your match.
- Weight Goal Targets
See estimated calories for lose, maintain, or gain.
- Gender-Specific
Formulas tailored for male and female physiology.
- 100% Private
All calculations run in your browser. No data is uploaded.