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🔥 Basal Metabolic Rate (BMR) Calculator

Uses the Mifflin-St Jeor formula to work out your BMR and the calories you need each day for your activity level.

📚 What Is Basal Metabolic Rate?

  • Meaning — The smallest amount of energy your body needs at complete rest to stay alive (breathing, heartbeat, keeping your body temperature, and so on).
  • Age and BMR — As we age, we lose muscle, so BMR goes down too. People in their 60s have a BMR about 15 to 20% lower than people in their 20s.
  • The role of muscle — 1 kg of muscle burns about 3 times more calories than 1 kg of fat. This is why strength exercise matters for keeping your metabolism up.
  • The formula — This calculator uses the Mifflin-St Jeor formula, which is considered one of the most accurate.
💡 A note for older adults: Do not cut back too much on food just because your BMR is low, as this speeds up muscle loss. It is more important to eat enough protein and exercise regularly.