1. What is Body Fat Percentage?

Body fat percentage is the total mass of fat divided by total body mass, multiplied by 100. It provides a more accurate assessment of body composition than BMI alone, as it distinguishes between fat mass and lean body mass.

2. How Does the Calculator Work?

The calculator uses the UK NHS body fat percentage formula:

Where:

• \( BMI \) — Body Mass Index (unitless)
• \( age \) — Age in years
• \( sex \) — 1 for female, 0 for male

Explanation: This formula estimates body fat percentage based on BMI, age, and gender, providing a quick assessment of body composition.

3. Importance of Body Fat Percentage

Details: Monitoring body fat percentage is important for assessing health risks associated with obesity, tracking fitness progress, and maintaining optimal body composition for overall health.

4. Using the Calculator

Tips: Enter your BMI value (calculate separately 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: What is a healthy body fat percentage range?
A: For men: 8-19% (athletes), 20-24% (fitness), 25%+ (obese). For women: 21-33% (athletes), 34-39% (fitness), 40%+ (obese).

Q2: How accurate is this calculation method?
A: This formula provides a reasonable estimate but may not be as accurate as methods like DEXA scans or hydrostatic weighing.

Q3: Why does the formula include age and gender?
A: Body fat distribution changes with age, and men and women naturally have different body fat percentages due to physiological differences.

Q4: How often should I measure my body fat percentage?
A: For most people, measuring every 4-8 weeks is sufficient to track changes without becoming obsessive about daily fluctuations.

Q5: Can this calculator be used for athletes?
A: While it provides a general estimate, athletes may benefit from more precise measurement methods due to their unique body composition.