Fat Calculator – Estimate Your Body Fat Percentage
The Body Fat Calculator helps you estimate your body fat percentage based on standard methods using your age, gender, height, weight, and optionally waist, neck, and hip measurements. It’s a useful tool for anyone looking to track fitness progress, plan workouts, or monitor their health goals.
How to Use the Body Fat Calculator
Provide the following details:
- Your age and gender
- Height and weight
- Waist and neck measurements (and hip for females)
The calculator uses either the US Navy Method or BMI method to estimate your body fat %.
Body Fat Calculation Formula
US Navy Method:
For males:
Body Fat % = 86.010 × log10(waist − neck) − 70.041 × log10(height) + 36.76
For females:
Body Fat % = 163.205 × log10(waist + hip − neck) − 97.684 × log10(height) − 78.387
Example
A 28-year-old male, 5'10" tall (178 cm), weighing 75 kg, with 34-inch waist and 15-inch neck:
→ Estimated Body Fat: ~17.5%
→ Fitness Category: Fit
Common Use Cases
- Tracking body composition changes over time
- Fitness goal setting (cutting, bulking)
- Monitoring weight loss or fat loss
- Health risk analysis (visceral fat, obesity)
- Nutrition and calorie planning
Why Use a Body Fat Calculator?
While weight alone doesn’t reflect health, body fat % gives a more accurate view of fitness and risk factors. This tool helps track progress more reliably than BMI or scales alone.
Frequently Asked Questions (FAQs)
Which method is more accurate — BMI or Navy?
The US Navy Method is more accurate for fat % than BMI, which only uses height and weight.
Do I need a tape measure?
Yes, for more accurate results, you should measure waist, neck, and hip (for females).
Can this replace a DEXA scan?
No, it provides an estimate. For clinical accuracy, use tools like DEXA or hydrostatic weighing.
Is body fat the same as BMI?
No. BMI is based on weight and height. Body fat percentage reflects the actual fat in your body.
What is a healthy fat percentage?
For males: 10–20% is healthy. For females: 18–28%. Athletes tend to be lower.
Related tools: BMI Calculator, Calorie Calculator, BMR Calculator.