FatCalc

Body Fat Calculator

This body fat calculator can estimate what percentage of your body is fat and tells you how much you would need to weigh for a healthy amount of body fat. The calculator uses the U.S. Navy, Covert Bailey, Jackson-Pollock, Durnin-Womersley, and BMI formulas to calculate body fat percentage.

Body Fat Calculator

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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 to put yourself in a desirable healthy body fat percentage range.

What is a good body fat percentage?

Generally, a good body fat percentage range for women is 21 to 35 percent, and for men, it's 8 to 24 percent depending on age. Your resting metabolic rate changes as you age; fat mass increases while muscle mass decreases. Thus, the low end of the range would apply to younger adults and then trend upwards with age. The range values were derived from a study by Dympna Gallagher et al. on a new approach for developing healthy body fat percentage ranges for adults. It links healthy body mass index (BMI) guidelines with predicted body fat percentages.

How to Estimate Body Fat?

Accurate means of measuring body fat exist, such as Dual-Energy X-ray Absorptiometry (DEXA), air-displacement plethysmography, and hydrostatic weighing, but they can be expensive and inconvenient. This 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 only need a flexible measuring tape or a good quality skinfold caliper.

You can choose an estimation method from the calculator's drop-down list. If you already know your body fat percentage and are confident of its accuracy, you can simply enter the value manually and then note your status in the charts provided. You can choose the BMI method where only your height and weight measurements are required. For the U.S. Navy and Covert Bailey methods, you will require a flexible measuring tape to measure the circumferences of various areas of your body. For the Jackson-Pollock and Durnin-Womersley methods, you will need a skinfold caliper to measure the skinfold thickness at several sites on your body.

BMI (Body Mass Index) Estimation Method

The BMI method calculates body fat percentage based on age, sex, height, and weight. It is the least accurate of all the methods. It only gives a ballpark estimate for those who don't want to bother with measuring tapes or skinfold calipers. Note also that it's only intended for individuals living a sedentary lifestyle.

Circumference Measuring Methods

Circumference measurements, used in the U.S. Navy and Covert Bailey methods, offer an easy and reliable way to measure body fat. Both methods require a flexible and nonstretchable measuring tape to measure the circumferences around specific body areas. All measurements are taken against the bare skin with tape measurements made parallel to the floor with the exact amount of tension at the same spot each time. The tape must be snug against the skin but not enough to compress the underlying soft tissues. All measurements, including height and weight, should be made in thin underclothes and without shoes. Measurements must be taken at the same time of day before any physical activity to provide a consistent estimate to chart your progress.

U.S. Navy Method

The U.S. Navy developed an excellent formula using body circumference measurements to determine the fat content in a person's body. This calculation considers all service members, as they must meet specific percent standards regarding body fat percentage.

Neck, waist and hip circumference measurements are required for women. The hip measurement is not required for men. Waist measurements are taken at the belly button for men and just above the belly button for women. You can click on the help (?) icon next to the input fields in the calculator to get specific details.

The accuracy of the U.S. Navy Body Circumference method is around 3.5% for most people.

Covert Bailey Method

The Covert Bailey Method is named after its creator, fitness expert Covert Bailey. Bailey has been a leading voice in the fitness industry for over 30 years, and countless people worldwide have used Bailey's method of calculating body fat percentage. It's considered one of the most recent formulas to measure body fat.

According to Bailey, for most people, the tape-measure test's accuracy is within 2.0% of the measurement you would get through a hydrostatic weighing or immersion test.

Skinfold Measurement Methods

Personal trainers commonly use skinfold measurements to estimate body fat in local gyms. Using skinfold calipers require some training and experience for maximal efficacy and 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.

Refer to the 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 probably 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, 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 WHO / NIH 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 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 diet, you can help minimize the loss of muscle mass through weight training exercises and increased protein intake.

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References

  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
  9. Bailey, Covert. The Ultimate Fit Or Fat . HarperCollins. Kindle Edition.