Caloric Needs Calculator
Understanding Your Caloric Needs
Knowing how many calories your body requires is the fundamental first step in any fitness journey, whether you want to lose fat, build muscle, or maintain your current physique. Our caloric calculator uses the Mifflin-St Jeor Equation, which is widely considered the most accurate formula for predicting Basal Metabolic Rate (BMR) in healthy individuals.
What is BMR and TDEE?
Basal Metabolic Rate (BMR): This is the amount of energy (calories) your body needs to function while at complete rest. This includes vital functions like breathing, circulating blood, and cell production.
Total Daily Energy Expenditure (TDEE): This is the total number of calories you burn in a day, including your BMR plus the energy used for physical activity. This is your "maintenance" level.
How the Calculation Works
The calculator follows these specific formulas:
- For Men: BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) + 5
- For Women: BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) – 161
Once the BMR is calculated, we multiply it by an activity factor to find your TDEE:
| Activity Level | Multiplier | Description |
|---|---|---|
| Sedentary | 1.2 | Desk job, very little movement |
| Lightly Active | 1.375 | Light exercise 1-3 times a week |
| Moderately Active | 1.55 | Moderate exercise 3-5 times a week |
| Very Active | 1.725 | Hard exercise 6-7 days a week |
Example Calculation
Let's look at a 30-year-old male, weighing 80kg, 180cm tall, who is moderately active:
- BMR: (10 × 80) + (6.25 × 180) – (5 × 30) + 5 = 1,780 calories.
- TDEE: 1,780 × 1.55 = 2,759 calories.
- To lose 0.5kg per week, he would subtract 500 calories, aiming for roughly 2,259 calories per day.
Adjusting for Your Goals
If your goal is weight loss, a safe and sustainable deficit is typically 500 calories below your TDEE. Conversely, if you are looking to gain weight or build muscle, a surplus of 250 to 500 calories above maintenance is generally recommended to minimize excessive fat gain.