BMR Calculator
Calculate your Basal Metabolic Rate — calories your body burns at rest.
BMR and TDEE are estimates. Individual metabolic rates vary. Consult a registered dietitian or healthcare provider before making significant dietary changes.
BMR (at rest)
TDEE (with activity)
For Weight Loss
TDEE − 500 kcal
How It Works
Enter your age, gender, weight, and height. The calculator uses the Mifflin-St Jeor equation to compute your BMR and Total Daily Energy Expenditure (TDEE) based on your activity level.
**BMR Calculator — Know Your Metabolic Baseline**
Your Basal Metabolic Rate (BMR) is the number of calories your body needs to maintain basic physiological functions at complete rest — breathing, circulation, cell production, and temperature regulation. It represents the minimum calories required to keep you alive.
**BMR Equations**
Our calculator uses the Mifflin-St Jeor equation (1990), the most accurate formula for most adults:
**Men:** BMR = 10 × weight(kg) + 6.25 × height(cm) – 5 × age(years) + 5
**Women:** BMR = 10 × weight(kg) + 6.25 × height(cm) – 5 × age(years) – 161
Alternatively, the older Harris-Benedict equation (revised 1984) is also widely used.
**TDEE — Total Daily Energy Expenditure**
BMR alone doesn't account for activity. Multiply BMR by your Physical Activity Level (PAL) multiplier:
| Activity Level | Multiplier |
|---|---|
| Sedentary (desk job, little exercise) | × 1.2 |
| Lightly active (1–3 days/week exercise) | × 1.375 |
| Moderately active (3–5 days/week) | × 1.55 |
| Very active (6–7 days/week) | × 1.725 |
| Extra active (physical job + exercise) | × 1.9 |
**How to Use TDEE for Weight Goals**
- **Maintain weight:** Eat at TDEE
- **Lose weight:** Eat 500 kcal below TDEE (loses ~0.5kg/week)
- **Lose weight faster:** Eat 1000 kcal below TDEE (loses ~1kg/week)
- **Gain muscle:** Eat 250–500 kcal above TDEE (lean bulk)
**Never eat below your BMR** without medical supervision — it can trigger metabolic adaptation, nutrient deficiencies, and muscle loss.
**Factors That Affect BMR**
- Age (BMR decreases ~2% per decade after 20)
- Muscle mass (higher muscle = higher BMR)
- Thyroid function (hypothyroidism lowers BMR significantly)
- Hormones (testosterone, oestrogen, cortisol)
- Temperature (cold environments slightly raise BMR)