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Advanced BMR & TDEE Calculator

Calculate your Basal Metabolic Rate and Total Daily Energy Expenditure using the Mifflin-St Jeor equation. Supports kg/lbs and cm/ft+in inputs.

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Understanding BMR and TDEE

Your Basal Metabolic Rate (BMR) is the number of calories your body needs to perform basic life-sustaining functions like breathing, circulation, and cell production while at complete rest. It accounts for approximately 60-75% of your total daily calorie expenditure.

Total Daily Energy Expenditure (TDEE) takes your BMR and multiplies it by an activity factor to estimate how many calories you actually burn in a day. This is the number you need to know whether your goal is weight loss, maintenance, or muscle gain.

The Mifflin-St Jeor Equation

This calculator uses the Mifflin-St Jeor equation, which research has shown to be the most accurate formula for estimating BMR. It is more accurate than the older Harris-Benedict equation, especially for overweight and obese individuals.

For men: BMR = (10 x weight in kg) + (6.25 x height in cm) - (5 x age) + 5

For women: BMR = (10 x weight in kg) + (6.25 x height in cm) - (5 x age) - 161

Activity Level Multipliers

  • Sedentary (1.2): Desk job, little or no exercise
  • Light Exercise (1.375): Light exercise 1-2 days per week
  • Moderate Exercise (1.55): Moderate exercise 3-5 days per week
  • Very Active (1.725): Hard exercise 6-7 days per week
  • Extra Active (1.9): Athlete, intense training, or physical job

A common approach for safe weight loss is to create a 500-calorie daily deficit, which results in approximately 0.5 kg (1 pound) of weight loss per week. For weight gain, a 500-calorie surplus promotes steady muscle growth when combined with resistance training.

Frequently Asked Questions

BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest to maintain vital functions. TDEE (Total Daily Energy Expenditure) is BMR multiplied by your activity level, representing your actual daily calorie needs.
This calculator uses the Mifflin-St Jeor equation, widely regarded as the most accurate formula for estimating BMR. For men: BMR = (10 x weight) + (6.25 x height) - (5 x age) + 5. For women: BMR = (10 x weight) + (6.25 x height) - (5 x age) - 161.
To lose weight, eat 500 calories below your TDEE for approximately 0.5 kg (1 lb) loss per week. To gain weight, eat 500 calories above your TDEE. Always consult a healthcare professional before making significant dietary changes.
Sedentary (desk job): 1.2, Light exercise (1-2 days/week): 1.375, Moderate exercise (3-5 days/week): 1.55, Very active (6-7 days/week): 1.725, Extra active (athlete/physical job): 1.9.

Last updated: June 2026