BMR & TDEE Calculator (Basal Metabolic Rate)

Understanding BMR & TDEE

**Basal Metabolic Rate (BMR)** is the minimum number of calories required to sustain the body's vital functions at rest, such as breathing, blood circulation, and maintaining body temperature. This value accounts for roughly 60-75% of your daily calorie burn.

BMR Formulas Explained

Two primary formulas are used to estimate BMR:

• **Mifflin-St Jeor Equation (Recommended):** Developed in the early 1990s, this is currently the most accurate predictive BMR equation, particularly for modern populations. $$\text{BMR} (\text{Male}) = (10 \times \text{Weight}_\text{kg}) + (6.25 \times \text{Height}_\text{cm}) - (5 \times \text{Age}) + 5$$ $$\text{BMR} (\text{Female}) = (10 \times \text{Weight}_\text{kg}) + (6.25 \times \text{Height}_\text{cm}) - (5 \times \text{Age}) - 161$$
• **Revised Harris-Benedict Equation:** A classic formula (originally 1919, revised 1984) that is still widely used but can sometimes overestimate BMR in sedentary individuals. $$\text{BMR} (\text{Male}) = 66.5 + (13.75 \times \text{Weight}_\text{kg}) + (5.003 \times \text{Height}_\text{cm}) - (6.75 \times \text{Age})$$ $$\text{BMR} (\text{Female}) = 655.1 + (9.563 \times \text{Weight}_\text{kg}) + (1.850 \times \text{Height}_\text{cm}) - (4.676 \times \text{Age})$$

Calculating Total Daily Energy Expenditure (TDEE)

**TDEE** is the total number of calories you burn each day. It is calculated by multiplying your BMR by an **Activity Multiplier** based on your lifestyle, incorporating exercise and general daily movement. TDEE is your **maintenance calories**—the amount needed to stay the same weight.