Body Fat Percentage Calculator
Estimate your body fat percentage from your height, neck, waist, and weight. See where you fall in the standard ranges, how much of your weight is fat, and how much you would lose to reach a goal.
Your estimate
Estimated body fat
16.1%
Fitness range for men. Tape measure (US Navy) method.
- Fat mass
- 12.9 kg
- Lean mass
- 67.1 kg
- BMI
- 24.7 (Healthy weight)
- BMI estimate
- 22.3%
Body fat ranges for men
| Category | Body fat | Your result |
|---|---|---|
| Essential fat | 2–5% | |
| Athletes | 6–13% | |
| Fitness | 14–17% | You are here |
| Average | 18–24% | |
| Obese | 25% and above |
Ranges are from the American Council on Exercise.
This is an estimate, not a medical measurement, and it can be off by several percentage points. It cannot replace advice from a doctor or dietitian. Muscular people may get a higher estimate than their real body fat.
What is body fat percentage?
Your body fat percentage is the share of your weight that is fat. The rest is lean mass: muscle, bone, organs, and water. Some fat is essential, because your body uses it for energy, hormones, and protecting organs. This free body fat calculator estimates your percentage from simple measurements. You can use the tape measure (US Navy) method with your height, neck, and waist, plus your hip if you are a woman, or the BMI, age, and sex method with your height and weight. It then shows where you fall in the standard ranges, your fat and lean mass, and how much fat you would lose to reach a goal.
How to use the body fat calculator
- Choose your units and sex. Switch between metric and imperial at any time, and your numbers are converted.
- Pick a method. Tape measure is the default. The BMI method needs only your age, height, and weight.
- Enter your measurements. The "How to measure" tips explain how to place the tape for your neck, waist, and hip.
- Add a goal (optional). Enter a target body fat and your weight to see how much fat you would lose to reach it.
- Read your result. You get your estimate, the range it falls in, fat and lean mass, BMI, and a table of the ranges.
How the two methods work
The tape measure (US Navy) method estimates body density from your height and the difference between your waist and neck measurements. For women, it uses waist plus hip minus neck. It then converts density to a body fat percentage. It does not need your weight or age.
The BMI, age, and sex method uses a formula that combines your BMI, your age, and your sex:
Body fat % = −44.988 + 0.503 × age + 10.689 × sex + 3.172 × BMI − 0.026 × BMI² + 0.181 × BMI × sex − 0.02 × BMI × age − 0.005 × BMI² × sex + 0.00021 × BMI² × age
Here sex is 0 for men and 1 for women, and BMI is weight in kilograms divided by height in metres squared. The study behind this formula reports an average error of roughly 4.7 percentage points, and it is built for adults. Because BMI cannot tell muscle from fat, it is the less precise choice for very muscular people.
Worked examples
These results come straight from the calculator.
| Person | Method | Body fat | Range |
|---|---|---|---|
| Man, age 35, 180 cm, 80 kg, neck 38 cm, waist 85 cm | Tape measure | 16.1% | Fitness |
| Woman, 165 cm, 62 kg, neck 32 cm, waist 74 cm, hip 98 cm | Tape measure | 28.4% | Average |
| Man, age 42, 172 cm, 84 kg | BMI | 28.5% | Obese |
| Man, 5 ft 10 in, 180 lb, neck 15 in, waist 34 in | Tape measure | 17.4% | Fitness |
Body fat percentage chart
These ranges are from the American Council on Exercise. Women have higher ranges because they need more essential fat.
| Category | Women | Men |
|---|---|---|
| Essential fat | 10–13% | 2–5% |
| Athletes | 14–20% | 6–13% |
| Fitness | 21–24% | 14–17% |
| Average | 25–31% | 18–24% |
| Obese | 32% and above | 25% and above |
Why body fat matters for your health
- Higher body fat is linked with a greater risk of heart disease and type 2 diabetes, especially when fat is carried around the waist.
- Too little body fat can disturb hormones, and in women it can affect periods and fertility.
- Body fat shows more about your health than weight alone, because two people with the same weight can have very different amounts of fat and muscle.
How to measure accurately
- Use a flexible tape, keep it level and snug, and do not squeeze the skin.
- Measure in the morning, before eating, and in the same way each time.
- Take each measurement twice and use the average. A 1 cm error in the waist can shift the result noticeably.
- Do not tense or flare your neck, and breathe out normally when you measure your waist.
Other ways to measure body fat
- Skinfold calipers
- A trained person pinches the skin at set places and measures its thickness.
- Bioelectrical impedance
- Scales and handheld devices send a weak current through the body. Results depend on hydration.
- Hydrostatic (underwater) weighing
- Compares your weight in air and in water to work out your density.
- DXA scan
- A low-dose X-ray scan that separates fat, lean tissue, and bone.
- Ultrasound
- Uses sound waves to measure the thickness of the fat layer under the skin.
How to reduce body fat
- Combine strength training with cardio. Lifting weights helps you keep muscle while you lose fat.
- Aim for a moderate, steady change instead of a crash diet. Very low calorie intakes make it harder to keep muscle and stick to the plan.
- Choose whole foods such as vegetables, fruit, lean protein, and whole grains most of the time, and go easy on sweets and fatty snacks.
- Drink plenty of water and track your progress with the same measurements every few weeks.
- Talk to a doctor or dietitian before starting a diet, especially if you have a health condition.
What this calculator can and cannot do
It estimates body fat for adults from measurements you provide. It is not a medical measurement and it cannot replace a doctor’s assessment. The estimate can be off by several percentage points, and it may overstate body fat in muscular people. The fat-to-lose figure assumes that you keep your lean mass. Do not use it for children or during pregnancy.
Body fat terms explained
- Body fat percentage
- The share of your total body weight that is fat.
- Essential fat
- The minimum fat the body needs for normal function.
- Storage fat
- Fat stored under the skin and around organs. It is the fat you can gain or lose.
- Lean mass
- Everything that is not fat: muscle, bone, organs, and water.
- BMI
- Weight in kilograms divided by height in metres squared.
Related calculators
See more tools on the health and fitness calculators page, or track what you eat with theChipotle nutrition calculator.
Frequently asked questions
What is a healthy body fat percentage?
It depends on your sex and goals. Using the American Council on Exercise ranges, men are in the fitness range at 14–17% and the average range at 18–24%, and women are in the fitness range at 21–24% and the average range at 25–31%. Women need more essential fat than men, so their ranges are higher. A doctor can tell you what is healthy for you.
Which method should I use, tape measure or BMI?
Use the tape measure (US Navy) method if you can take the measurements, because it uses your waist and neck, which reflect where you carry fat. The BMI, age, and sex method needs only your height and weight, but it cannot tell muscle from fat, so it is less reliable for very muscular or very lean people. If you fill in everything, the calculator shows both so that you can compare.
How accurate is the body fat calculator?
It gives an estimate that can be off by several percentage points. Formulas based on measurements are useful for tracking change over time with the same method, but they are not a medical test. Methods such as DXA scans measure body composition more directly.
How do I measure my neck, waist, and hips?
Use a flexible tape and keep it level and snug without squeezing. Measure your neck just below the Adam’s apple. Men measure the waist at the navel, and women measure it at the narrowest part of the waist. Women also measure the hips at the widest part. Take each measurement twice and use the average.
Can athletes and muscular people use it?
With care. The BMI method treats extra muscle as extra fat, so it can overstate body fat in muscular people. The tape measure method does better, but it is still an estimate. For athletes, skinfold calipers or a DXA scan give a more reliable picture.
What is essential body fat?
Essential fat is the minimum your body needs for normal function, including hormones, organ protection, and energy. It is about 2–5% for men and 10–13% for women on the ranges used here. Staying below it for long can harm your health.
Do body fat scales work?
They estimate body fat by sending a small, harmless electrical current through your body and measuring the resistance, which depends on how much water you hold. Readings change with hydration, meals, and exercise, so use one at the same time each day and look at trends instead of single readings.
Is body fat percentage better than BMI?
They answer different questions. BMI compares your weight with your height and cannot tell fat from muscle. Body fat percentage shows how much of your weight is fat, so it is more informative for people with a lot of muscle. Neither one is a diagnosis.
How quickly can I safely lose body fat?
Gradual loss is easier to keep and easier on your body. A common guideline is to aim for about 0.5–1 kg (1–2 lb) of weight loss per week at most. Avoid crash diets, do not eat so little that you lose muscle, and ask a doctor or dietitian before you start.
How is the fat to lose to reach my goal worked out?
The calculator assumes you keep your lean mass. Your lean mass is your weight minus your fat mass. The weight at your goal is lean mass ÷ (1 − goal body fat). The fat to lose is your current weight minus that weight. In real life you may also lose a little muscle, so treat it as a guide.
Why do the two methods give different results?
They use different inputs. The tape measure method looks at body shape, and the BMI method uses weight for height, age, and sex. A person with a lot of muscle or a different fat distribution can get quite different numbers. If they differ a lot, check your measurements, and do not rely on one number alone.