Body Fat Calculator

Use this body fat calculator to estimate what percentage of your body weight is fat and discover how much you would need to weigh for a healthy amount of body fat. The calculator uses formulas based on the U.S. Navy, BMI, and skinfold measurement methods.

Body Fat Calculator


The calculator integrates your results with charts developed by three well-known health and fitness organizations. They will show your status at your current weight. You can then plan for a goal weight that will put you in a desired healthy body fat percentage range.

How to Estimate Body Fat?

Accurate measuring of body fat exists, such as Dual-Energy X-ray Absorptiometry (DEXA), air-displacement plethysmography, and hydrostatic weighing, but they can be expensive and inconvenient. This free online body fat calculator will give you a quick and reasonable estimate of your body fat percentage using readily available tools in the comfort of your own home.

You can choose different measurement methods from the calculator's drop-down list to calculate your body fat percentage; one based on your Body Mass Index, a body circumference method developed by the U.S. Navy, and four skinfold measurement methods. If you already know your body fat percentage and are confident of its accuracy, you can enter the value manually. You can then note your status in the charts.

Estimate from BMI

This method calculates body fat percentage from Body Mass Index (BMI) using regression equations. The formula takes gender and age into consideration.

This estimation is not as accurate as body circumference or skinfold methods. It does, however, give a ballpark estimate for those of you who don't want to bother with measuring tapes or skinfold calipers. Note also that it's only intended for sedentary individuals.

U.S. Navy Body Circumference Measures

This method requires circumference measurements at the neck, waist, and hips. Use a measuring tape made of nonstretchable material, preferably fiberglass. Measure your circumferences parallel to the floor, applying the same amount of tension at the same spot each time you make a measurement. Don't compress the underlying soft tissues. All measurements, including height and weight, should be made in thin underclothes and without shoes. This method will provide you with a consistent estimate to chart your progress.

Circumference measurements are taken differently for men and women. The formula does not require hip measurements for men. Take waist measurements at the belly button for men and above the belly button for women. Click on the help (?) icon next to the input fields for measurement details.

The accuracy of the U.S. Navy Body Circumference method is comparable to skinfold methods, around 3.5% for most people.

Skinfold Measurement Methods

Skinfold testing can predict body fat percentages within plus or minus 3.5 percent of your actual body composition. Generally, the more skinfold sites measured, the greater the accuracy. However, the U.S. Navy body circumference method and skinfold testing can lose accuracy for obese or extremely lean individuals.

For skinfold measurements, please refer to your skinfold caliper manual for instructions. As a general rule, always take skinfold measurements from the right side of the body.

Take a minimum of two measurements at each skinfold site. If the two measurements differ by more than 2 mm, take a 3rd. Record the average for the site. Click the help (?) icon next to the input fields for info on the exact location of the skinfold measurement.

Jackson-Pollock 3-Site Skinfold Method

This skinfold method uses simple measurements that you can perform yourself. It is reasonably accurate for most people with an average build. However, it underestimates body fat for athletes, bodybuilders, or very lean individuals. The formula uses the chest, abdomen, and thigh for men and the tricep, suprailiac, and thigh for women.

Jackson-Pollock 4-Site Skinfold Method

With this method, the skinfold measurement sites are the same for males and females. Measurements are taken at four sites, making this method slightly more reliable than the three sites, but it loses accuracy for very lean individuals.

Jackson-Pollock 7-Site Skinfold Method

This method produces the most reliable results of the three Jackson-Pollock series of skinfold measurements. The test uses seven skinfold sites, the same for males and females.

Durnin-Womersley Skinfold Method

The Durnin-Womersley method is probably the most popular skinfold measurement method used, but it overestimates body fat for very fit individuals. It utilizes four skinfold measurements at the same four skinfold sites for males and females.

Body Fat Percentage Calculation Results

The calculations will show your body fat percentage status in charts developed by the American Council on Exercise, the NIH Health / Guidelines, and the American College of Sports Medicine.

The tables include a weight column showing a calculated weight range for each body fat percentage range. From it, you can ascertain what you would need to weigh to fall into the desired category. The weight ranges are only accurate if you gain or lose weight in such a way as to maintain your current lean body mass. In essence, the weight ranges reflect only changes in body fat. In reality, your lean body mass changes along with your body fat mass, but to a lesser degree. As you lose or gain weight, you may want to periodically recalculate your body fat percentage and select a new target weight if required to stay on track. On a low-calorie carbohydrate diet, you can help minimize the loss of muscle mass through weight training exercises and increased protein intake.

Related Calculators


  1. World Health Organization. Obesity and overweight
  2. Hodgdon, James & Friedl, Karl. (1999). Development of the DoD Body Composition Estimation Equations. 28.
  3. Jackson AS, Stanforth PR, Gagnon J, et al. The effect of sex, age and race on estimating percentage body fat from body mass index. The Heritage Family Study. Int J Obes Relat Metab Disord. 2002;26(6):789-796. doi:10.1038/sj.ijo.0802006
  4. Gallagher D, Heymsfield SB, Heo M, Jebb SA, Murgatroyd PR, Sakamoto Y. Healthy percentage body fat ranges: An approach for developing guidelines based on body mass index. Am J Clin Nutr. 2000;72(3):694-701. doi:10.1093/ajcn/72.3.694
  5. Hall KD. Body fat and fat-free mass inter-relationships: Forbes's theory revisited. Br J Nutr. 2007;97(6):1059-1063. doi:10.1017/S0007114507691946
  6. Willoughby D, Hewlings S, Kalman D. Body Composition Changes in Weight Loss: Strategies and Supplementation for Maintaining Lean Body Mass, a Brief Review. Nutrients. 2018;10(12):1876. Published 2018 Dec 3. doi:10.3390/nu10121876
  7. Medicine, A. S. (20170830). ACSM's Health-Related Physical Fitness Assessment, 5th Edition. [[VitalSource Bookshelf version]]. Retrieved from vbk://9781496391636
  8. St-Onge MP, Gallagher D. Body composition changes with aging: the cause or the result of alterations in metabolic rate and macronutrient oxidation?Nutrition. 2010;26(2):152-155. doi:10.1016/j.nut.2009.07.004