1. What is TDEE?

TDEE (Total Daily Energy Expenditure) represents the total number of calories you burn in a day, including basal metabolic rate and physical activity. For muscle gain, you need to consume more calories than your TDEE.

2. How Does the Calculator Work?

The calculator uses the Mifflin-St Jeor equation for BMR:

Where s = +5 for males, -161 for females

TDEE = BMR × activity multiplier
Calories for Muscle Gain = TDEE + 500

Activity Multipliers:

• Sedentary: 1.2 (little to no exercise)
• Light: 1.375 (light exercise 1-3 days/week)
• Moderate: 1.55 (moderate exercise 3-5 days/week)
• Active: 1.725 (hard exercise 6-7 days/week)
• Very Active: 1.9 (very hard exercise, physical job)

3. Importance of TDEE Calculation

Details: Accurate TDEE calculation is crucial for effective muscle building. A 500-calorie surplus above TDEE provides the extra energy needed for muscle growth while minimizing fat gain.

4. Using the Calculator

Tips: Enter weight in kg, height in cm, age in years, select gender and activity level. All values must be valid (weight > 0, height > 0, age between 1-120).

5. Frequently Asked Questions (FAQ)

Q1: Why add 500 calories for muscle gain?
A: A 500-calorie surplus provides enough energy for muscle growth while minimizing excess fat accumulation.

Q2: How accurate is the Mifflin-St Jeor equation?
A: It's one of the most accurate BMR equations for healthy adults, with about 90% accuracy.

Q3: Should I adjust my calories over time?
A: Yes, as you gain weight and muscle mass, your TDEE increases and you may need to adjust your calorie intake.

Q4: What if I'm not gaining muscle?
A: Ensure you're following a proper strength training program and getting adequate protein (1.6-2.2g/kg body weight).

Q5: Can this calculator be used for weight loss?
A: For weight loss, you would subtract 500 calories from your TDEE instead of adding.