Calculate your Basal Metabolic Rate — calories your body burns at complete rest. The foundation of all calorie and diet planning.
A Basal Metabolic Rate (BMR) Calculator estimates the number of calories your body needs to maintain basic physiological functions while at complete rest — breathing, circulation, cell production and temperature regulation. BMR is the starting point for all calorie planning, whether for weight loss, maintenance or muscle gain.
BMR represents 60–75% of total daily energy expenditure for most sedentary individuals. It is influenced by age (decreases with age), sex (men have higher BMR due to more muscle mass), body composition (more muscle = higher BMR), genetics and thyroid function. Knowing your BMR allows you to calculate your Total Daily Energy Expenditure (TDEE) by multiplying by an activity factor.
| Age Group | Male BMR (avg) | Female BMR (avg) | Change per Decade |
|---|---|---|---|
| 20–30 years | 1,800–2,000 | 1,400–1,600 | Baseline |
| 30–40 years | 1,750–1,950 | 1,350–1,550 | −50–100 kcal |
| 40–50 years | 1,700–1,900 | 1,300–1,500 | −50–100 kcal |
| 50–60 years | 1,600–1,800 | 1,250–1,450 | −100 kcal |
BMR per unit of lean mass is a metabolic efficiency indicator. Higher BMR relative to body weight indicates greater metabolic rate, typically associated with more muscle mass. The "Metabolic Age" concept compares your BMR to the average BMR for your chronological age — a younger metabolic age means a higher BMR relative to peers.
Enter your weight, height, age and gender. Click Calculate to see your BMR from two validated formulas. Use this number to calculate your TDEE by using our TDEE Calculator, which multiplies BMR by an activity factor.
All BMR formulas are estimates with a margin of error of ±10%. They do not account for individual genetic variation, muscle fibre type, hormonal conditions or medications. Conditions like hypothyroidism can significantly lower BMR. The most accurate BMR measurement requires indirect calorimetry in a clinical setting.