BMR Calculator

The Mifflin-St Jeor estimate of resting energy expenditure is 1780 kcal/day for a male person aged 30, 80 kg and 180 cm.

How it works

• Applied the sex-specific Mifflin-St Jeor constant (+5 for male, −161 for female).
• Multiplied the weight by 10 and the height by 6.25.
• Subtracted five times the age and added the constant, then rounded to whole kcal.

BMR = 10 × weight + 6.25 × height − 5 × age + 5 = 10 × 80 + 6.25 × 180 − 5 × 30 + 5

• This is an estimate of resting energy expenditure, not a measured value.
• It excludes physical activity; multiplying by an activity factor gives only a rough daily estimate.
• This is not medical or dietary advice; a clinician or dietitian can assess your needs.

Methodology

1. Mifflin-St Jeor: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age (years) + s, where s = +5 for male and −161 for female.
2. Round the result to whole kcal/day.
3. The equation estimates resting energy expenditure for a general adult population and is not a prescription.

Usage

1. Choose biological sex as used by the equation.
2. Enter your age in years.
3. Enter your weight in kilograms and your height in centimetres, then read the estimated BMR.

Examples

These are examples, not current values: they use fixed inputs, while the interactive tool computes live results in your browser.

Male 30y, 80 kg, 180 cm

{
  "sex": "male",
  "age": 30,
  "weight": 80,
  "height": 180
}

Female 45y, 65 kg, 165 cm

{
  "sex": "female",
  "age": 45,
  "weight": 65,
  "height": 165
}

Male 20y, 70 kg, 175 cm

{
  "sex": "male",
  "age": 20,
  "weight": 70,
  "height": 175
}

Limitations

About the equation

The Mifflin-St Jeor equation (1990) is one of the most accurate simple predictive equations for resting energy expenditure in healthy adults and is widely used in clinical and sports settings. It is a regression, so it estimates an average rather than measuring an individual. This page presents the estimate transparently and makes no target or medical claim.

Disclaimer

This calculator is an estimate for information only and is not medical or dietary advice. It cannot assess your individual metabolism and it does not prescribe a calorie intake. Consult a qualified healthcare professional or dietitian for personal guidance.