1. What is TDEE?

Total Daily Energy Expenditure (TDEE) is an estimate of how many calories you burn per day when exercise is taken into account. It's calculated by first estimating your Basal Metabolic Rate (BMR), then multiplying that value by an activity factor.

2. How Does the Calculator Work?

The calculator uses the Mifflin-St Jeor Equation for BMR and multiplies it by an activity factor:

Where BMR is calculated as:

• For men: \( BMR = (10 \times weight) + (6.25 \times height) - (5 \times age) + 5 \)
• For women: \( BMR = (10 \times weight) + (6.25 \times height) - (5 \times age) - 161 \)

Activity Factors:

• Sedentary (little or no exercise): 1.2
• Lightly active (light exercise 1-3 days/week): 1.375
• Moderately active (moderate exercise 3-5 days/week): 1.55
• Very active (hard exercise 6-7 days/week): 1.725
• Extra active (very hard exercise & physical job): 1.9

3. Importance of TDEE Calculation

Details: Knowing your TDEE helps with weight management - consuming fewer calories than your TDEE leads to weight loss, while consuming more leads to weight gain.

4. Using the Calculator

Tips: Enter your 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 use Mifflin-St Jeor instead of Harris-Benedict?
A: The Mifflin-St Jeor equation is considered more accurate for most people in modern times.

Q2: How accurate is this calculator?
A: It provides a good estimate, but individual variations in metabolism can make actual TDEE different by ±10-15%.

Q3: Should I use metric or imperial units?
A: The calculator uses metric units (kg, cm) for better accuracy in the equations.

Q4: How often should I recalculate my TDEE?
A: Recalculate whenever your weight changes significantly (5+ kg) or your activity level changes substantially.

Q5: Can I use this for weight loss?
A: Yes, subtract 300-500 kcal from your TDEE for steady weight loss (about 0.5kg per week).