1. What is BMR?

Basal Metabolic Rate (BMR) is the number of calories your body needs to maintain basic physiological functions at rest. It accounts for 60-75% of daily calorie expenditure.

2. How Does the Calculator Work?

The calculator uses the Mifflin-St Jeor Equation:

Where:

• \( weight \) — Body weight in kilograms
• \( height \) — Height in centimeters
• \( age \) — Age in years
• \( gender\_factor \) — +5 for men, -161 for women
• \( activity \) — Activity level multiplier

Explanation: The equation estimates your resting calorie needs, then adjusts for activity level and creates a 500-calorie deficit for weight loss.

3. Importance of BMR Calculation

Details: Knowing your BMR helps create personalized diet plans for weight loss, maintenance, or gain. A 500-calorie daily deficit typically results in about 0.5kg (1lb) weight loss per week.

4. Using the Calculator

Tips: Enter your weight in kg, height in cm, and accurate age. Select your gender and typical activity level. For best results, measure weight in the morning after using the bathroom.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this calculator?
A: The Mifflin-St Jeor equation is about 90% accurate for most people. For exact measurements, metabolic testing is needed.

Q2: Why subtract 500 calories?
A: A 500-calorie daily deficit creates about 0.5kg (1lb) of weight loss per week, which is considered safe and sustainable.

Q3: Should I eat below my BMR?
A: Generally no - eating below BMR can slow metabolism. The calculator already creates a deficit from your total daily energy expenditure.

Q4: How often should I recalculate?
A: Recalculate every 5-10kg of weight loss, as BMR decreases with weight loss.

Q5: What if I'm not losing weight at this calorie level?
A: You may need to adjust your activity level or reduce calories slightly, but consult a professional before going below 1200 kcal/day (women) or 1500 kcal/day (men).