1. What is the Mifflin-St Jeor Formula?

The Mifflin-St Jeor formula is a widely used equation for estimating Basal Metabolic Rate (BMR), which represents the number of calories your body needs at rest. When multiplied by an activity factor, it calculates Total Daily Energy Expenditure (TDEE) - the total calories you burn in a day.

2. How Does the Calculator Work?

The calculator uses the Mifflin-St Jeor formula:

Where:

• \( weight \) — Body weight in kilograms (kg)
• \( height \) — Height in centimeters (cm)
• \( age \) — Age in years
• \( activity\ factor \) — Multiplier based on activity level (1.2-1.9)

Explanation: The formula calculates BMR first, then multiplies by an activity factor to estimate total daily calorie needs.

3. Importance of TDEE Calculation

Details: Knowing your TDEE is essential for weight management - it helps determine appropriate calorie intake for weight loss, maintenance, or muscle gain goals.

4. Using the Calculator

Tips: Enter weight in kg, height in cm, age in years, and select your appropriate activity level. All values must be valid positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is the Mifflin-St Jeor formula?
A: It's considered one of the most accurate BMR formulas for the general population, with about 90% accuracy for most individuals.

Q2: What are the activity factor categories?
A: Sedentary (1.2), Lightly active (1.375), Moderately active (1.55), Very active (1.725), Extra active (1.9).

Q3: Should I use this for weight loss planning?
A: Yes, TDEE calculation is fundamental for creating effective weight loss or gain plans by establishing your maintenance calorie level.

Q4: Are there limitations to this formula?
A: It may be less accurate for extremely muscular individuals, those with very high body fat percentages, or elderly populations.

Q5: How often should I recalculate my TDEE?
A: Recalculate whenever your weight changes significantly (5+ kg) or your activity level changes substantially.