Body Fat Percentage Calculator
Body Fat Calculator
Estimate your body fat percentage using the U.S. Navy Method
Body Fat Percentage Categories
| Category | Men | Women |
|---|---|---|
| Essential Fat | 2–5% | 10–13% |
| Athletes | 6–13% | 14–20% |
| Fitness | 14–17% | 21–24% |
| Average | 18–24% | 25–31% |
| High | 25%+ | 32%+ |
Body Fat Calculator
Use our free Body Fat Calculator to estimate your body fat percentage based on your age, gender, height, weight, and body measurements.
The calculator uses the U.S. Navy Body Fat Formula, a circumference-based method that estimates body fat percentage from measurements such as waist, neck, and hip circumference.
You can use the calculator with Metric Units, US Units, or Other Units.
What Is Body Fat Percentage?
Body fat percentage is the proportion of your total body weight that consists of fat.
For example, if someone weighs 80 kg and has a body fat percentage of 20%, approximately 16 kg of their body weight would be fat, while the remaining 64 kg would be lean mass.
Body fat is an important component of the human body. Some body fat is essential for normal physiological functions, while excess body fat can be associated with increased health risks.
How Does the Body Fat Calculator Work?
Our calculator uses the U.S. Navy Method, which estimates body fat from body circumference measurements.
For men, the calculation uses:
- Height
- Neck circumference
- Waist circumference
- Weight
- Age and gender for additional calculations
For women, the calculation additionally uses:
- Hip circumference
The calculator converts measurements into a consistent unit system before applying the body-fat equation.
Because this is an estimation method, the result should be treated as an approximate body-fat percentage rather than an exact measurement.
How to Measure Yourself Correctly
Accurate measurements can make the estimate more useful. Use a flexible measuring tape and avoid pulling the tape excessively tight.
Neck Measurement
Place the measuring tape around the neck without compressing the skin.
Keep the tape reasonably level and take the measurement in a relaxed position.
Waist Measurement
For men, measure around the abdomen according to the method recommended for the calculator.
For women, measure around the natural waist or the appropriate waist location used by the selected body-fat method.
Keep the tape horizontal and avoid sucking in your stomach.
Hip Measurement
Hip circumference is required for the female calculation.
Measure around the widest part of the hips and buttocks while standing normally.
Height
Measure your height without shoes.
Stand upright with your feet flat and your head in a neutral position.
Weight
For the most consistent results, weigh yourself under similar conditions each time you track your progress.
Body Fat Percentage Categories
Body-fat ranges differ between men and women because typical body composition is different.
| Category | Men | Women |
|---|---|---|
| Essential Fat | 2–5% | 10–13% |
| Athletes | 6–13% | 14–20% |
| Fitness | 14–17% | 21–24% |
| Average | 18–24% | 25–31% |
| Higher Body Fat | 25%+ | 32%+ |
These ranges are general reference categories rather than medical diagnoses. Different organizations and research sources may use slightly different ranges.
What Is Essential Body Fat?
Essential body fat is the minimum amount of fat needed for normal physiological function.
Fat plays important roles in:
- Hormone production
- Cell structure
- Protection of internal organs
- Energy storage
- Absorption of certain vitamins
- Temperature regulation
Trying to reduce body fat to extremely low levels is not necessarily healthier and can be harmful.
Body Fat Mass vs Lean Body Mass
Your total body weight can be broadly divided into fat mass and lean body mass.
Body Fat Mass
Body fat mass is the estimated amount of your body weight that consists of fat.
For example:
80 kg body weight × 20% body fat = 16 kg fat mass
Lean Body Mass
Lean body mass is your total body weight minus estimated fat mass.
Using the example above:
80 kg − 16 kg = 64 kg lean body mass
Lean body mass includes muscle, bones, organs, water, connective tissue, and other non-fat components.
Body Fat Percentage vs BMI
BMI and body fat percentage are not the same measurement.
BMI is calculated from height and weight:
BMI = Weight ÷ Height²
Body fat percentage attempts to estimate how much of your total weight consists of fat.
A person with a high amount of muscle can have a relatively high BMI while having a relatively low body-fat percentage.
This is one reason BMI and body-fat percentage can provide different information.
Can You Have a Normal BMI but High Body Fat?
Yes.
BMI does not directly measure body fat. A person can fall within a normal BMI range while carrying a relatively high percentage of body fat.
Conversely, someone who has substantial muscle mass may have a high BMI without having a high body-fat percentage.
For a more complete picture, body composition, waist circumference, fitness, lifestyle, and other health measurements can be considered.
How Accurate Is the Body Fat Calculator?
The U.S. Navy method provides an estimate, not a direct measurement.
The result can be affected by:
- Measurement technique
- Measuring-tape position
- Hydration
- Body shape
- Fat distribution
- Muscle development
- Individual differences in body composition
For this reason, don't treat a single calculator result as an exact body-fat measurement.
If you are tracking progress, it can be more useful to measure yourself under similar conditions and look at the trend over time rather than focusing on a single number.
How to Track Body Fat Progress
If your goal is to monitor changes in body composition, try to keep your measurements consistent.
For example:
- Measure at approximately the same time of day.
- Use the same measuring tape.
- Measure at the same anatomical locations.
- Avoid intentionally pulling the tape tighter between measurements.
- Record your measurements and calculated body-fat percentage.
- Compare results over several weeks rather than reacting to one measurement.
Consistency is more useful than chasing tiny changes in individual readings.
What Is a Healthy Body Fat Percentage?
There isn't one universal body-fat percentage that is ideal for every person.
Healthy body-fat levels can vary according to:
- Sex
- Age
- Genetics
- Physical activity
- Fitness level
- Individual health status
Athletes may have considerably different body composition from the general population.
Rather than trying to reach an extremely low percentage, focus on a body composition that is appropriate for your individual circumstances and health goals.
Body Fat Calculator Formula
The U.S. Navy method uses logarithmic equations based on circumference measurements.
Men
The commonly used equation is:
Body Fat % = 86.010 × log10(waist − neck) − 70.041 × log10(height) + 36.76
Measurements are expressed in inches for this equation.
Women
The commonly used equation is:
Body Fat % = 163.205 × log10(waist + hip − neck) − 97.684 × log10(height) − 78.387
Measurements are expressed in inches.
Our calculator handles the necessary unit conversion automatically when you use Metric or other measurement options.
Frequently Asked Questions
What is body fat percentage?
Body fat percentage is the estimated percentage of your total body weight that consists of fat.
What is a good body fat percentage?
There isn't one ideal number for everyone. Typical body-fat ranges vary according to sex, age, genetics, and activity level.
How is body fat calculated?
Our calculator uses the U.S. Navy circumference method, which estimates body fat using measurements such as height, waist, neck, and, for women, hip circumference.
Do women need to enter hip measurements?
Yes. The U.S. Navy equation for women includes hip circumference, so the calculator requires it for the female calculation.
Can I use centimeters and kilograms?
Yes. Select Metric Units and enter your measurements in centimeters and kilograms.
Can I use feet, inches, and pounds?
Yes. Select US Units and enter height in feet and inches, weight in pounds, and your circumference measurements in inches.
Is the U.S. Navy method accurate?
It provides a useful estimate, but it is not as direct as laboratory or clinical body-composition methods. Measurement technique can also affect the result.
Does body fat percentage change with age?
Body composition generally changes with age, and typical body-fat levels can differ across age groups. Your calculator result should therefore be interpreted in the context of your age and sex.
Is body fat more important than BMI?
BMI and body-fat percentage measure different things. Neither should automatically be considered "more important" for every person. BMI is a simple height-and-weight screening measure, while body-fat percentage attempts to estimate the proportion of body weight that is fat.
Body Fat Calculator Results
Our calculator provides several useful estimates, including:
- Body Fat Percentage
- Body Fat Mass
- Lean Body Mass
- BMI
- BMI-based Body Fat Estimate
- Reference Body Fat Percentage
- Difference from the Reference Level
These measurements can help you understand your body composition and monitor changes over time.
Important Disclaimer
This calculator is provided for general informational and educational purposes.
The body-fat percentage produced by this calculator is an estimate and should not be considered a medical diagnosis or a substitute for professional medical advice.
If you have concerns about your body composition, weight, nutrition, or health, consult a qualified healthcare professional.
Calculate Your Body Fat
Enter your age, gender, height, weight, neck circumference, waist circumference, and, when required, hip circumference in the calculator above to estimate your body-fat percentage.
For the most useful comparison over time, take your measurements consistently and track the trend rather than relying on a single result.