1. What is Body Fat Percentage?

Body Fat Percentage (BFP) is the total mass of fat divided by total body mass, expressed as a percentage. It provides a more accurate measure of fitness than BMI alone, as it distinguishes between fat mass and lean body mass.

2. How Does the Calculator Work?

The calculator uses the BMI-based equation:

Where:

• \( BMI \) — Body Mass Index (kg/m²)
• \( Age \) — Age in years
• 1.20, 0.23 — Empirical coefficients
• -16.2/-5.4 — Gender-specific constants

Explanation: The equation estimates body fat percentage based on BMI and age, with different constants for men and women.

3. Importance of Body Fat Percentage

Details: Knowing your body fat percentage helps assess health risks, track fitness progress, and set appropriate weight loss or muscle gain goals.

4. Using the Calculator

Tips: Enter your BMI (calculate it first if needed), age in years, and select your gender. All values must be valid (BMI > 0, age between 1-120).

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this method?
A: It provides a reasonable estimate (±3-5%) but is less accurate than methods like DEXA scans or skinfold measurements.

Q2: What are healthy body fat percentages?
A: For men: 6-24% (athletes 6-13%, fitness 14-17%, average 18-24%). For women: 16-30% (athletes 14-20%, fitness 21-24%, average 25-30%).

Q3: Why does age affect body fat percentage?
A: Metabolism slows with age, and people tend to lose muscle mass, leading to higher body fat percentage at the same weight.

Q4: Are there limitations to this equation?
A: Less accurate for very muscular individuals, elderly, or those with extremely high/low BMI.

Q5: How often should I measure my body fat percentage?
A: Every 4-8 weeks is sufficient to track meaningful changes, as body fat changes slowly.