Direct Answer: To calculate your daily caloric requirement, multiply your Basal Metabolic Rate (BMR) by an activity factor from 1.2 to 1.9. Eat below this number to lose fat or above it to build muscle mass.
Calculate your TDEE (Total Daily Energy Expenditure) based on your metrics and activity level.
Mifflin-St Jeor Equation × Activity Factor| Variable | Description & Context | Measurement Unit | Sample Input |
|---|---|---|---|
Gender |
Gender | Standard | male |
Age |
Age | Standard | 25 |
Weight |
Weight (kg) | kg | 70 |
Height |
Height (cm) | cm | 175 |
Activity Level |
Activity Level | Standard | e.g. 100 |
Understanding these foundational concepts ensures you interpret your results with precision:
Mastering your calorie intake is the science behind body transformation. Whether you want to lose fat or gain muscle, it all starts with your "Maintenance Calories."
Weight management is a simple equation: Energy In vs. Energy Out. This calculator finds your TDEE, which is the amount of energy you burn in a full day. To lose weight, aim for a "deficit"—roughly 500 calories below your TDEE is a sustainable target for most.
Be honest about your activity level! Many people overestimate how active they are. If you work a desk job but walk for 30 minutes, you are likely "Lightly Active" rather than "Moderate."
Male, 25, 70kg, 175cm, Sedentary ≈ 2,000 kcal/day
| Computation Step | Formula / Input Parameter | Calculated Output |
|---|---|---|
| 1. Applied Formula | Mifflin-St Jeor Equation × Activity Factor |
Mathematical Standard |
| 2. Applied Scenario | Male, 25, 70kg, 175cm, Sedentary ≈ 2,000 kcal/day | Standard Calculation Run |
| 3. Final Result | Verified Calculation Output | Computed Output |
Learn the difference between these vital health numbers and how to use them for your fitness goals.
Read the Full Guide: Health Metrics 101: BMI, BMR, and TDEE Explained →