Body fat calculator
Enter the measurements you have, from a skinfold caliper, a tape measure or just weight, height and waist, and see the result of every method they allow, with the category, fat mass and lean mass. Free, no sign-up.
Updated
Skinfolds
In millimeters, with a skinfold caliper. All optional: each method uses its own.
Diagonal fold between the armpit and the nipple: halfway in men, a third of the way from the armpit in women.
Vertical fold below the armpit, level with the bottom of the breastbone.
Vertical fold on the back of the upper arm, halfway between shoulder and elbow.
Vertical fold on the front of the upper arm, halfway between shoulder and elbow.
Diagonal fold at 45 degrees, 1 to 2 cm below the tip of the shoulder blade.
Vertical fold 2 cm to the side of the navel.
Diagonal fold just above the iliac crest, on the line down from the front of the armpit. Used by Jackson-Pollock.
Fold just above the iliac crest, on the line down from the middle of the armpit. Used by Durnin-Womersley.
Vertical fold on the front of the thigh, halfway between the hip crease and the knee.
Vertical fold on the inside of the lower leg, where the calf is widest.
Circumferences
In centimeters, with a tape measure, without compressing the skin. All optional.
Just below the Adam's apple.
At the narrowest point, about halfway between the bottom of the breastbone and the navel. Used by the US Navy method for women.
At navel level. Used by the US Navy method for men, and by Cicone.
Level with the top of the hip bone (iliac crest), at the end of a normal breath out. Used by RFM.
At the widest part of the buttocks.
Result
- Body fat
- Category
- Fat mass
- Lean mass
To see the result, enter: sex and age.
Are you a trainer or nutritionist? In MyFitnessClient, assessments keep your client's skinfolds, calculate body fat and show how each measurement changes over time.
Create a free accountFind a professionalIn short
This calculator estimates body fat percentage with published equations, each from the measurements of its own study: skinfolds, circumferences, or just weight, height and waist. None of them measures fat, and each has its own standard error: according to their authors, about 3.5 to 3.7 percentage points for the US Navy, 4.1 for Deurenberg and 4.7 for CUN-BAE. The methods give different values, so to track someone's progress, always use the same one, measured the same way. It is an estimate for adults, not a clinical diagnosis, and the athletes' equations are only for male athletes.
How it's calculated
Each method is a published equation, built on the measurements and the people of its own study. Each one's formulas, with their authors and year, are further down, under “Each method's formulas”.
Where to measure
Skinfolds are measured with a caliper on the right side of the body, with the person standing and relaxed; circumferences with a tape measure, without compressing the skin. Each method uses the sites from its own study: the suprailiac and the iliac crest, for example, are different skinfolds.
Skinfolds
- Chest
- Diagonal fold between the armpit and the nipple: halfway in men, a third of the way from the armpit in women.
- Midaxillary
- Vertical fold below the armpit, level with the bottom of the breastbone.
- Triceps
- Vertical fold on the back of the upper arm, halfway between shoulder and elbow.
- Biceps
- Vertical fold on the front of the upper arm, halfway between shoulder and elbow.
- Subscapular
- Diagonal fold at 45 degrees, 1 to 2 cm below the tip of the shoulder blade.
- Abdominal
- Vertical fold 2 cm to the side of the navel.
- Suprailiac
- Diagonal fold just above the iliac crest, on the line down from the front of the armpit. Used by Jackson-Pollock.
- Iliac crest
- Fold just above the iliac crest, on the line down from the middle of the armpit. Used by Durnin-Womersley.
- Thigh
- Vertical fold on the front of the thigh, halfway between the hip crease and the knee.
- Calf
- Vertical fold on the inside of the lower leg, where the calf is widest.
Circumferences
- Neck
- Just below the Adam's apple.
- Waist
- At the narrowest point, about halfway between the bottom of the breastbone and the navel. Used by the US Navy method for women.
- Abdomen
- At navel level. Used by the US Navy method for men, and by Cicone.
- Waist at the iliac crest
- Level with the top of the hip bone (iliac crest), at the end of a normal breath out. Used by RFM.
- Hips
- At the widest part of the buttocks.
Category, fat mass and lean mass
The category combines two sources. At the lean end it follows the American Council on Exercise (ACE) body fat chart, a widely shared reference chart rather than a study, the same at every age: essential fat (below 6% in men and 14% in women), athlete (below 14% and 21%) and fit (below 18% and 25%). From there up, normal, overweight and obese follow the cut-offs of Gallagher and colleagues (2000), which change with sex and age. Fat mass and lean mass come from body weight:
- Fat mass = weight × body fat % ÷ 100
- Lean mass = weight − fat mass
Example
A 32-year-old man, 78 kg and 178 cm tall, measured everything the calculator asks for.
- Skinfolds, in mm: chest 12, midaxillary 14, triceps 15, biceps 6, subscapular 16, abdominal 22, suprailiac 15, iliac crest 18, thigh 18, calf 10.
- Circumferences, in cm: neck 38, waist 84, abdomen 88, waist at the iliac crest 90, hips 98.
| Jackson-Pollock, 7 skinfolds | 16.6% |
|---|---|
| Jackson-Pollock, 3 skinfolds | 15.9% |
| Jackson-Pollock, 3 skinfolds (chest, triceps, subscapular) | 17.7% |
| Jackson-Pollock, 4 skinfolds (1985) | 17.4% |
| Durnin-Womersley, 4 skinfolds | 22.5% |
| Peterson (2003) | 24.7% |
| Cicone (2021) | 17.9% |
| Sloan | 17.2% |
| Wilmore-Behnke | 17.5% |
| US Navy | 18.7% |
| Relative Fat Mass (RFM) | 24.4% |
| Deurenberg (BMI) | 20.7% |
| CUN-BAE | 21.8% |
With the same measurements, the methods range from 15.9% to 24.7%. That's why, to track progress, you should always use the same one.
More about the calculator
Skinfold caliper
With a skinfold caliper, skinfolds in millimeters. Most equations give body density (D), which the Siri equation (1961) converts to body fat percentage:
- body fat % = 495 ÷ D − 450
Jackson-Pollock, 7 skinfolds
- Men: D = 1.112 − 0.00043499 × S + 0.00000055 × S² − 0.00028826 × age
- Women: D = 1.097 − 0.00046971 × S + 0.00000056 × S² − 0.00012828 × age
S is the sum of the 7 skinfolds, in millimeters: chest, midaxillary, triceps, subscapular, abdominal, suprailiac and thigh. Built on 308 men aged 18 to 61 and 249 women aged 18 to 55; for women, the authors advise caution over age 40.
Studies: Jackson and Pollock (1978); Jackson, Pollock, and Ward (1980).
Jackson-Pollock, 3 skinfolds
- Men: D = 1.10938 − 0.0008267 × S + 0.0000016 × S² − 0.0002574 × age
- Women: D = 1.0994921 − 0.0009929 × S + 0.0000023 × S² − 0.0001392 × age
S is the sum of 3 skinfolds, in millimeters: chest, abdominal and thigh in men; triceps, suprailiac and thigh in women. Same samples and ages as the 7 skinfolds.
Studies: Jackson and Pollock (1978); Jackson, Pollock, and Ward (1980).
Jackson-Pollock, 3 skinfolds (chest, triceps, subscapular)
- Men: D = 1.1125025 − 0.0013125 × S + 0.0000055 × S² − 0.000244 × age
Men only. S is the sum of chest, triceps and subscapular, in millimeters. The coefficients were checked against two independent sources; the study's sample and ages were not confirmed.
Studies: Jackson and Pollock (1985); Pollock, Schmidt, and Jackson (1980).
Jackson-Pollock, 4 skinfolds (1985)
- Men: body fat % = 0.29288 × S − 0.0005 × S² + 0.15845 × age − 5.76377
- Women: body fat % = 0.29669 × S − 0.00043 × S² + 0.02963 × age + 1.4072
S is the sum of triceps, abdominal, suprailiac and thigh, in millimeters. It gives body fat percentage directly, without body density. The sample and ages of the 1985 paper were not confirmed in the original.
Study: Jackson and Pollock (1985).
Jackson-Pollock, 3 skinfolds (triceps, abdominal, suprailiac)
- Women: body fat % = 0.41563 × S − 0.00112 × S² + 0.03661 × age + 4.03653
Women only. S is the sum of triceps, abdominal and suprailiac, in millimeters. It gives body fat percentage directly, without body density. This is not the 1980 3-skinfold equation (triceps, suprailiac and thigh). The sample and ages of the 1985 paper were not confirmed in the original.
Study: Jackson and Pollock (1985).
Durnin-Womersley, 4 skinfolds
- Men aged 17 to 19: D = 1.1620 − 0.0630 × log(S)
- Men aged 20 to 29: D = 1.1631 − 0.0632 × log(S)
- Men aged 30 to 39: D = 1.1422 − 0.0544 × log(S)
- Men aged 40 to 49: D = 1.1620 − 0.0700 × log(S)
- Men aged 50 and over: D = 1.1715 − 0.0779 × log(S)
- Women aged 16 to 19: D = 1.1549 − 0.0678 × log(S)
- Women aged 20 to 29: D = 1.1599 − 0.0717 × log(S)
- Women aged 30 to 39: D = 1.1423 − 0.0632 × log(S)
- Women aged 40 to 49: D = 1.1333 − 0.0612 × log(S)
- Women aged 50 and over: D = 1.1339 − 0.0645 × log(S)
S is the sum of biceps, triceps, subscapular and iliac crest, in millimeters, and log is the base-10 logarithm. One equation per sex and age band, built on 209 men aged 17 to 72 and 272 women aged 16 to 68.
Study: Durnin and Womersley (1974).
Peterson (2003)
- Men: body fat % = 20.94878 + 0.1166 × age − 0.11666 × height + 0.42696 × S − 0.00159 × S²
- Women: body fat % = 22.18945 + 0.06368 × age + 0.60404 × BMI − 0.1452 × height + 0.30919 × S − 0.00099562 × S²
S is the sum of triceps, subscapular, suprailiac and thigh, in millimeters, and height goes in centimeters. It gives body fat percentage directly. Compared against a 4-compartment model in 681 white US adults aged 18 to 55, with a standard error of 4.6 to 5 percentage points. The exact site of the suprailiac skinfold was not confirmed in the original.
Study: Peterson, Czerwinski, and Siervogel (2003).
Cicone (2021)
- body fat % = 6.083 + 0.143 × S − 12.058 × sex − 0.150 × age − 0.233 × BMI + 0.256 × abdomen + 0.162 × sex × age
S is the sum of midaxillary, triceps and thigh, in millimeters, abdomen goes in centimeters, and sex is 1 for men and 0 for women. It gives body fat percentage directly. Compared against a 5-compartment model in adults aged 18 to 69, with a BMI of 15.7 to 49.5.
Study: Cicone et al. (2021).
Sloan
- Men: D = 1.1043 − 0.001327 × thigh − 0.00131 × subscapular
- Women: D = 1.0764 − 0.00081 × iliac crest − 0.00088 × triceps
Men: subscapular and thigh. Women: iliac crest and triceps. In millimeters. Built on young adults; the women's equation on 50 women aged 17 to 25. The exact site of the women's skinfold was not confirmed in the original.
Studies: Sloan (1967); Sloan, Burt, and Blyth (1962).
Wilmore-Behnke
- Men: D = 1.08543 − 0.000886 × abdominal − 0.0004 × thigh
- Women: D = 1.06234 − 0.00068 × subscapular − 0.00039 × triceps − 0.00025 × thigh
Men: abdominal and thigh. Women: subscapular, triceps and thigh. In millimeters. Built on young adult US university students in the 1960s; the exact ages were not confirmed.
Studies: Wilmore and Behnke (1969); Wilmore and Behnke (1970).
Katch-McArdle
- Men: D = 1.09665 − 0.00103 × triceps − 0.00056 × subscapular − 0.00054 × abdominal
Men only: triceps, subscapular and abdominal, in millimeters. Built on 53 male university students aged 18 to 24. This is not the Katch-McArdle formula for basal metabolic rate.
Study: Katch and McArdle (1973).
Tape measure
With a tape measure, circumferences and height in centimeters. log is the base-10 logarithm.
US Navy
- Men: body fat % = 495 ÷ (1.0324 − 0.19077 × log(abdomen − neck) + 0.15456 × log(height)) − 450
- Women: body fat % = 495 ÷ (1.29579 − 0.35004 × log(waist + hips − neck) + 0.22100 × log(height)) − 450
Men: neck, and abdomen at navel level. Women: neck, waist at its narrowest and hips. All in centimeters, with height. Built on US Navy personnel, 602 men aged 18 to 56 and 214 women aged 18 to 44, with a standard error of 3.5 percentage points in men and 3.7 in women.
Studies: Hodgdon and Beckett (1984); Hodgdon and Beckett (1984).
Weight, height and waist
Only weight, height and, for RFM, waist. BMI is weight in kilograms divided by height in meters squared.
Relative Fat Mass (RFM)
- Men: body fat % = 64 − 20 × height ÷ waist at the iliac crest
- Women: body fat % = 76 − 20 × height ÷ waist at the iliac crest
Height and waist at the iliac crest, in the same unit. It gives body fat percentage directly. Built on US adults aged 20 and over. The authors advise against it when height divided by waist is 3 or more.
Study: Woolcott and Bergman (2018).
Deurenberg (BMI)
- body fat % = 1.2 × BMI + 0.23 × age − 10.8 × sex − 5.4
Only BMI, age and sex, which is 1 for men and 0 for women. The study had 1,229 healthy Dutch people aged 7 to 83; this is the adult equation, from age 16. In the study, BMI ranged from 13.9 to 40.9, and this equation's standard error is 4.1 percentage points.
Study: Deurenberg, Weststrate, and Seidell (1991).
CUN-BAE
- 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
BMI, age and sex, which here is 1 for women and 0 for men. Built on 6,123 Caucasian adults aged 18 to 80, with a standard error of about 4.7 percentage points. The curve turns from a BMI of about 55 in women, and higher in men: from there on, more BMI gives less fat.
Studies: Gómez-Ambrosi et al. (2012); Gómez-Ambrosi et al. (2012).
Athletes
Equations built only on male athletes. For anyone else, use the methods above.
Reilly, soccer players
- Men: body fat % = 5.174 + 0.124 × thigh + 0.147 × abdominal + 0.196 × triceps + 0.130 × calf
Men only: thigh, abdominal, triceps and calf, in millimeters. It gives body fat percentage directly. Built on 45 professional soccer players, compared against DXA.
Study: Reilly et al. (2009).
Forsyth-Sinning, athletes
- Men: D = 1.10647 − 0.00162 × subscapular − 0.00144 × abdominal − 0.00077 × triceps + 0.00071 × midaxillary
Men only: subscapular, abdominal, triceps and midaxillary, in millimeters; midaxillary is the only one that is added rather than subtracted. Built only on male athletes; the exact sample was not confirmed.
Study: Forsyth and Sinning (1973).
- Jackson AS, Pollock ML (1978). Generalized equations for predicting body density of men. Br J Nutr 40(3):497-504.
- Jackson AS, Pollock ML, Ward A (1980). Generalized equations for predicting body density of women. Med Sci Sports Exerc 12(3):175-181.
- Siri WE (1961). Body composition from fluid spaces and density: analysis of methods. In: Brozek J, Henschel A, eds. Techniques for Measuring Body Composition. National Academy of Sciences, 223-244.
- Jackson AS, Pollock ML (1985). Practical assessment of body composition. Phys Sportsmed 13(5):76-90.
- Pollock ML, Schmidt DH, Jackson AS (1980). Measurement of cardio-respiratory fitness and body composition in the clinical setting. Compr Ther 6(9):12-27.
- Durnin JVGA, Womersley J (1974). Body fat assessed from total body density and its estimation from skinfold thickness: measurements on 481 men and women aged from 16 to 72 years. Br J Nutr 32(1):77-97.
- Peterson MJ, Czerwinski SA, Siervogel RM (2003). Development and validation of skinfold-thickness prediction equations with a 4-compartment model. Am J Clin Nutr 77(5):1186-1191.
- Cicone ZS, Nickerson BS, Choi YJ, Holmes CJ, Hornikel B, Fedewa MV, Esco MR (2021). Generalized equations for predicting percent body fat from anthropometric measures using a criterion five-compartment model. Med Sci Sports Exerc 53(12):2675-2682.
- Sloan AW (1967). Estimation of body fat in young men. J Appl Physiol 23(3):311-315.
- Sloan AW, Burt JJ, Blyth CS (1962). Estimation of body fat in young women. J Appl Physiol 17(6):967-970.
- Wilmore JH, Behnke AR (1969). An anthropometric estimation of body density and lean body weight in young men. J Appl Physiol 27(1):25-31.
- Wilmore JH, Behnke AR (1970). An anthropometric estimation of body density and lean body weight in young women. Am J Clin Nutr 23(3):267-274.
- Katch FI, McArdle WD (1973). Prediction of body density from simple anthropometric measurements in college-age men and women. Hum Biol 45(3):445-455.
- Hodgdon JA, Beckett MB (1984). Prediction of percent body fat for U.S. Navy men from body circumferences and height. Naval Health Research Center, Report No. 84-11.
- Hodgdon JA, Beckett MB (1984). Prediction of percent body fat for U.S. Navy women from body circumferences and height. Naval Health Research Center, Report No. 84-29.
- Woolcott OO, Bergman RN (2018). Relative fat mass (RFM) as a new estimator of whole-body fat percentage: a cross-sectional study in American adult individuals. Sci Rep 8:10980.
- Deurenberg P, Weststrate JA, Seidell JC (1991). Body mass index as a measure of body fatness: age- and sex-specific prediction formulas. Br J Nutr 65(2):105-114.
- Gómez-Ambrosi J, Silva C, Catalán V, Rodríguez A, Galofré JC, Escalada J, Valentí V, Rotellar F, Romero S, Ramírez B, Salvador J, Frühbeck G (2012). Clinical usefulness of a new equation for estimating body fat. Diabetes Care 35(2):383-388.
- Gómez-Ambrosi J, Silva C, Galofré JC, Escalada J, Santos S, Millán D, Vila N, Ibañez P, Gil MJ, Valentí V, Rotellar F, Ramírez B, Salvador J, Frühbeck G (2012). Body mass index classification misses subjects with increased cardiometabolic risk factors related to elevated adiposity. Int J Obes (Lond) 36(2):286-294.
- Reilly T, George K, Marfell-Jones M, Scott M, Sutton L, Wallace JA (2009). How well do skinfold equations predict percent body fat in elite soccer players? Int J Sports Med 30(8):607-613.
- Forsyth HL, Sinning WE (1973). The anthropometric estimation of body density and lean body weight of male athletes. Med Sci Sports 5(3):174-180.
- Gallagher D, Heymsfield SB, Heo M, Jebb SA, Murgatroyd PR, Sakamoto Y (2000). Healthy percentage body fat ranges: an approach for developing guidelines based on body mass index. Am J Clin Nutr 72(3):694-701.
- American Council on Exercise. Percent Body Fat Norms for Men and Women. ACE Fit, Percent Body Fat Calculator: Skinfold Method (archived 2023-12-01).
See also
TDEE and BMR calculator
BMR, the resting metabolic rate from the Mifflin-St Jeor equation, and total daily energy expenditure from the activity level.
Assessments
Measurements, skinfolds, bioimpedance and fitness tests, plus photos and videos from Basic up, with BMI, estimated body fat and assessment comparisons.