This body fat calculator helps you determine your body fat percentage by using your weight, height, and measurements, giving you a clear picture of your health and fitness level.
Body Fat Percentage Calculator
Calculate your body fat percentage using the Navy method formula
Your Body Fat Percentage
What is a Body Fat Percentage?
The total quantity of fat divided by the total mass of the body, then multiplied by 100, is the body fat percentage, or BFP. Since it is the only body measurement that determines a person’s relative body composition without taking into account height or weight, it acts as a gauge of fitness level.
How to Measure Body Fat
There are several methods to measure body fat percentage, varying in accuracy, accessibility, and cost:
- DEXA Scan (Dual-Energy X-ray Absorptiometry) – Considered the gold standard, this medical procedure uses X-rays to measure fat, muscle, and bone density with high accuracy.
- Hydrostatic Weighing – Underwater weighing that measures body density to calculate fat percentage.
- Skinfold Calipers -Determines the thickness of subcutaneous fat in particular body parts.
- Bioelectrical Impedance – Uses a weak electric current to estimate body fat based on how quickly the current travels through the body.
- Navy Method – The method used in this calculator, which uses circumference measurements of the neck, waist, and (for women) hips, along with height, to estimate body fat.
How to Use This Calculator
To get an estimate of your body fat percentage using the Navy Method:
- Select your own unit system (Metric or Imperial)
- Enter your gender, age, height, and weight
- Measure and enter your neck circumference (at the narrowest point)
- Take a measurement of your waist and enter it (at the narrowest point for women, at the navel for men).
- Only for women: Determine your hip circumference (at its broadest point) and enter it.
- Hit the “Calculate Body Fat” button to display your results
For men (metric):
BF% = 495 / (1.0324 – 0.19077 × log10(waist – neck) + 0.15456 × log10(height)) – 450
For women (metric):
BF% = 495 / (1.29579 – 0.35004 × log10(waist + hip – neck) + 0.22100 × log10(height)) – 450
For men (imperial):
BF% = 86.010 × log10(waist – neck) – 70.041 × log10(height) + 36.76
For women (imperial):
BF% = 163.205 × log10(waist + hip – neck) – 97.684 × log10(height) – 78.387
Body Fat Percentage Categories
Body fat percentages are categorized differently for men and women due to natural physiological differences.
| Category | Men | Women |
|---|---|---|
| Essential Fat | 2-5% | 10-13% |
| Athletic | 6-13% | 14-20% |
| Fitness | 14-17% | 21-24% |
| Average | 18-24% | 25-31% |
| Obese | 25%+ | 32%+ |
Why Body Fat Percentage Matters
Body fat percentage is a more accurate measure of health than BMI (Body Mass Index) because it distinguishes between fat and lean mass. A person with high muscle mass might be classified as overweight by BMI standards while maintaining a healthy body fat percentage.
Maintaining an appropriate body fat percentage is important for:
- Health and reduced risk of chronic diseases
- Hormone regulation and functioning
- Temperature regulation
- Organ protection
- Energy storage and insulation
The Navy Method is considered reasonably accurate with a standard error of estimate (SEE) of approximately 3-4% compared to more accurate methods like DEXA scans. This means your actual body fat percentage may be up to 3-4% higher or lower than the calculated result.
For most people, the Navy Method provides a good balance between accuracy and simplicity. It’s more accurate than BMI and simpler than methods requiring specialized equipment.
For most people, measuring body fat once every 4-8 weeks is sufficient to track changes. Body fat percentages don’t change dramatically in short periods, and frequent measurements can lead to unnecessary stress about minor fluctuations.
For consistency, try to measure at the same time of day (preferably in the morning), under similar conditions (before eating), and using the same measurement techniques and tools each time.
Reducing body fat percentage typically involves a combination of approaches:
- Caloric deficit: Consuming fewer calories than you burn
- Strength training: Building muscle to increase your metabolic rate
- Cardiovascular exercise: Burning calories and improving heart health
- Protein intake: Consuming adequate protein to preserve muscle mass during fat loss
- Sleep quality: Getting 7-9 hours of quality sleep per night
- Stress management: Reducing stress hormones that promote fat storage
A safe rate of fat loss is about 0.5-1% of body weight per week. More rapid weight loss often comes at the expense of muscle mass.
Yes, while athletic and lean body fat levels are often associated with health benefits, extremely low body fat percentages can be dangerous. Essential fat is necessary for normal physiological functions.
For men, body fat percentages below 5% and for women below 10% can lead to:
- Hormonal imbalances and reproductive issues
- Compromised immune function
- Cardiovascular problems
- Loss of menstruation in women
- Increased risk of osteoporosis
- Mental health issues including increased risk of eating disorders
Athletes may temporarily maintain very low body fat percentages for competitions, but this is not recommended for long-term health.
Subcutaneous fat is the fat stored directly under the skin that you can pinch. It’s the most visible type of fat and what most body fat measurements primarily assess.
Visceral fat is stored around your internal organs in the abdominal cavity. It’s less visible but more metabolically active and potentially more harmful to health when present in excess amounts.
Waist circumference is partially indicative of visceral fat levels, which is why the Navy Method includes this measurement. A large waist relative to other measurements can suggest higher levels of visceral fat, even in people with otherwise normal body fat percentages.