Body fat plays several critical roles in our body, including storing fuel for energy, regulating hormones, and protecting internal organs. However, having too much or too little body fat can be harmful to your health. So, what is the ideal body fat percentage, and how can you calculate it? Here is a web-based body fat percentage calculator and the formula behind it.
How to calculate body fat percentage?
Body fat is deposited in three places of your body and the areas are under the skin or subcutaneous, inside muscle tissue or intramuscular fat, and around internal organs or internal fat.
Though there are several ways to calculate body fat, the easiest method is to use an online body fat calculator like the one above. Even here you have two methods as Estimate method and Skinfold method.
Estimate method gives you a quick estimate of your body fat percentage using your gender, weight, and the circumference of your waist in case of men. Whereas for women, you have to additionally measure wrist, hips, and forearm.
It is believed that 50% of the fat lies under the skin and thus, the skinfold method is more accurate as it uses skin calipers to measure the thickness of the skinfold or subcutaneous fat at standardized sites of our body. However, this may not be true for obese people as they have more internal fat. Skinfold method won’t pick up internal fat.
You must take the following measurements and put it in above web-based body fat percentage calculator –
Weight yourself, preferably in the morning before breakfast and without your clothes.
Measure yourself with a tape measure at the largest part of your belly. Don’t pull in your stomach. The tape measure should be level and should not dig into the skin.
3. Wrist (Only for women)
Measure the smallest part of your wrist with a tape measure.
4. Forearm (Only for women)
Measure the thickest part of your arm below the elbow. Don’t bend your arm when you measure it and let it hand by your side.
5. Hip (Only for women)
Measure the largest point below your waist. Keep your feet together and remove your clothing.
Once you take all the measurements, input them into the body fat percentage calculator to get your body fat percentage. The calculator uses a different formula for men and women to calculate their body fat percentage.
Formula for women
Fat percentage = (((((Total bodyweight x 0.732) + 8.987) + (Wrist/3.14)) – (Waist x 0.157)) – (Hip x 0.249)) + (Forearm x 0.434)
Formula for men
Fat percentage = ((Bodyweight – (((Bodyweight x 1.082) + 94.42) – (Waist x 4.15)))*100)/Bodyweight
As we have told earlier, this method is more accurate than the estimate method. But for valid results, skinfold measurement has to be taken accurately and precisely at designated places of the body. Also, skinfold measurement should not be taken right after any exercise regime as the transfer of fluid to the skin may result in erroneous results. The procedure of taking skinfold measurement is as follows –
- Identify the location and take all measurement on the right side of your body
- Use your thumb and index finger of your left hand and grasp the skinfold
- Place the skin calipers pads perpendicular to the skinfold
- Release the grasp and measure the skinfold caliper dial close to 0.5 mm
Different anatomical body sites are measured for men and women as they differ in their patterns of storing body-fat.
Skinfold sites for men
- Chest – You have to measure the skinfold about halfway between the underarm crease and the nipple.
- Thigh – You have to measure vertical skinfold midway between the hip and knee on the front of the thigh.
- Abdomen – You have to measure the vertical skinfold about 1 inch lateral to the umbilicus or side of the navel.
Formula for men
Body fat percentage = 495 / (1.10938 – (0.0008267 x S) + (0.0000016 x S x S) – (0.0002574 x A)) – 450
S = Sum of 3 skinfold in mm
A = Age
Skinfold sites for women
- Triceps – You have to measure a vertical skinfold halfway between elbow and shoulder.
- Thigh – A vertical skinfold taken midway between the hip and knee joints on the front of the thigh.
- Suprailium or Suprailic – You have to measure a diagonal skinfold halfway between the hip joint and bottom of the rib cage.
Formula for women
Body fat percentage = 495 / (1.089733 – (0.0009245 x S) + (0.0000025 x S x S) – (0.0000979 x A)) – 450
S = Sum of 3 skinfold in mm
A = Age
Ideal body fat percentages
Once you have finished calculating your body fat percentage, you may be keen to know if your body fat is under acceptable range. The American Council on Exercise (ACE) (1) breaks up body fat percentage for men and women into different categories.
|Essential fat||10 to 13%|
|athletes||14 to 20%|
|Fitness||21 to 24%|
|Acceptable||25 to 31%|
|Obesity||32% and above|
|Essential fat||2 to 5%|
|athletes||6 to 13%|
|Fitness||14 to 17%|
|Acceptable||18 to 24%|
|Obesity||25% and above|
Is body fat percentage a better indicator of health than weight?
Many people depend on their bathroom scale to keep tabs on their weight and try to get into a better shape. However, bodyweight is not an accurate indicator of health. Two people of the same height and weight can have different body composition.
Body composition is the level of fat you have relative to your lean tissue (muscle, bones, water, and organs). Your body fat percentage gives a better indication of your body composition and health. When you have a lower body fat percentage, you have a higher lean mass and thus are healthier and fitter.
When you are trying to lose weight, you aim to lose body fat and to hold on to the lean mass. People sometimes lose muscle when they lose weight the wrong way. Ideally, you should lose excess fat and retain muscle mass as it is essential for your body and helps to boost your metabolism.
By measuring your body fat percentage, you can tell if your weight loss program is helping you to lose body fat and retain muscle mass.
Why control body fat?
While a small amount of body fat is essential for regulating hormones and protecting the body, excessive body fat can lead to many health problems. Research shows that men with higher than 25% body fat and women with higher than 32% of body fat have a higher risk of chronic illness and disease. These include –
1. Heart disease
High body fat levels can lead to high blood pressure and high cholesterol, which increases the risk of heart disease (1). Increased body fat can also lead to stroke, which is the third most common cause of death in the US.
High body fat is a well-known risk factor for type 2 diabetes. According to a study from the University of Florida, people with normal BMI but high levels of body fat are more prone to diabetes as compared to people who are overweight but have a low body fat percentage (2).
2. Pregnancy complications
Women with high body fat have a higher risk of developing pregnancy-related complications like premature birth, Caesarean delivery, or having children with health issues.
Alternative ways to measure body fat percentage
There are many ways to measure body fat percentage. Some are easy to use, while others require a trained professional. These include –
1. Bioelectric impedance
Bioelectric impedance devices pass a low powered current through the body to measure fat. The assessment is based on the level of water in the body as muscle holds more water than fat. This method is pain-free and harmless. This assessment may cost more but is easier compared to the calipers.
2. DeXA scanning
Dual-energy X-ray absorptiometry (DeXA) scan is a 10-minute test that takes a comprehensive snapshot of the breakdown of your muscle mass, fat tissue, and bone. It is highly accurate and is performed under medical settings by skilled technicians. It is also expensive and may not be available to all.
3. Hydrostatic weighing
Hydrostatic weighing measures a person’s body density using Archimedes’ Principle of displacement. During this test, the person has to fully immerse himself into a tank of water and hold their breath. While the test is relatively accurate, it is not easy to perform.
How to reduce body fat percentage?
Reducing weight is not the same as reducing body fat. Here are some of the best ways to reduce body fat –
1. Strength training
Strength training exercises require you to contract your muscles against resistance. They help reduce visceral fat and preserves fat-free mass.
Proteins help to reduce your appetite and aid in fat loss. A high-protein diet also helps to preserve muscle mass and metabolism during weight loss.
Healthy fats take longer to digest and help to slow down the emptying of your stomach, which helps to reduce appetite. Avoid unhealthy fats like trans fats.
Increasing your intake in high-fiber foods can help you to stay fuller and thus help in weight loss.
5. Do cardio exercises
Cardio exercises can increase muscle mass and decrease belly fat, waist circumference, and body fat.
Not all fat is bad. We need body fat for regulating hormones, protecting internal organs, and storing fuel for energy. However, excessive body fat can lead to many health problems. You can calculate your body fat percentage through online body fat calculators, skinfold calipers, bioelectric impedance, DeXA scanning, and hydrostatic weighing. To reduce your body fat percentage, you must follow a regimen that results in the loss of fat while maintaining muscle mass.