Body Fat Percentage Calculator

Our highly accurate Body Fat Calculator determines your total body fat percentage using precise body measurements. By default, it relies on the highly regarded US Navy method, alongside the widely used BMI (Body Mass Index) method, to estimate body composition. For the most accurate results, measure to the nearest 1/4 inch (or 0.5 cm). If you prefer the International System of Units, simply switch to the “Metric Units” (SI) tab.

Reference

The American Council on Exercise Body Fat Categorization

Jackson & Pollock Ideal Body Fat Percentages

Body Fat

"Adipose tissue" is the scientific term for body fat, and it serves a variety of vital functions in the human body. Its primary role is to store lipids, which the body relies on for energy. Adipose tissue also produces and regulates essential hormones while providing necessary cushioning and protection for your internal organs.

Your total body fat percentage is made up of two distinct types: essential fat and storage fat. Essential body fat is found in almost every part of the body. As the name suggests, it is absolutely vital for maintaining life and ensuring your reproductive and immune systems function properly. Men and women require different levels of essential fat: men naturally hold about 2–5%, while women require 10–13%.

Generally, a healthy body fat range is 8-19% for men and 21-33% for women. Carrying excess body fat can lead to severe health complications, but having an insufficient amount of body fat is also highly dangerous. If you are aiming for a body fat percentage below the essential range, you should consult a healthcare professional immediately.

Storage fat is the non-essential fat that accumulates in your adipose tissue. Anatomically, storage fat is divided into two categories: subcutaneous fat, which sits just beneath the skin, and visceral fat, which wraps around vital organs deep within the abdominal cavity.

While having some storage fat is healthy and necessary for energy reserves, excessive amounts can trigger significant health issues. It is important to note that being "overweight" does not automatically mean you have too much body fat. A person’s overall body composition is a combination of muscle mass, bone density, water weight, and body fat.

The rate at which you gain or lose body fat varies greatly from person to person. It depends on multiple factors, including genetics, diet, and lifestyle habits like physical activity. Numerous studies confirm that a balanced diet and consistent exercise are the most effective ways to manage weight. However, due to individual biological differences, some people may find it more difficult to lose stubborn belly fat.

Men and women accumulate and distribute body fat differently. Men typically store excess fat in the abdominal region, whereas women tend to carry it in the hips, thighs, and buttocks. After the age of 40, naturally declining sex hormone levels can lead to an increase in body fat. In women, this metabolic shift is especially common after menopause.

Excess Body Fat and Its Consequences

The World Health Organization (WHO) classifies obesity as one of the leading preventable causes of death worldwide. In the United States alone, excess weight and obesity significantly increase overall mortality risk by nearly 18%, causing over 500,000 deaths annually and potentially reducing life expectancy by 2 to 4 years.

High body fat percentages and obesity are linked to a diminished quality of life, poorer psychological well-being, and conditions like obstructive sleep apnea. More alarmingly, excess body fat is a primary risk factor for global mortality drivers, including cardiovascular disease, stroke, type 2 diabetes, and certain forms of cancer.

Because adipose tissue produces and regulates critical hormones, carrying an excess or lack of body fat disrupts this delicate balance. Clinical studies demonstrate that excess body fat—particularly abdominal visceral fat—impairs normal hormone function and metabolic activity.

Visceral fat is directly linked to insulin resistance, low levels of HDL ("good") cholesterol, and high levels of LDL ("bad") cholesterol. High LDL cholesterol contributes to dangerous plaque buildup in the arteries, drastically increasing the risk of heart attacks and coronary issues.

Furthermore, visceral fat secretes inflammatory cytokines—proteins involved in cell communication—that further elevate cardiovascular risks. When cells stop responding properly to insulin, a condition known as insulin resistance develops. This causes chronically elevated blood sugar levels, ultimately leading to type 2 diabetes and highly detrimental health consequences.

Body Fat Percentage Calculation

The US Navy's Approach

There are several methods used to calculate body fat. Our calculator utilizes the highly regarded equation-based method developed by Hodgdon and Beckett in 1984 at the Naval Health Research Center. Below are the precise measurement techniques and formulas used in the US Navy body fat calculations.

For men: Measure the circumference of the waistline at a horizontal level right across the navel. Ensure the tape measure is level and the stomach is fully relaxed—do not pull the stomach inward to guarantee precise measurements.

For women: Measure the waist at its narrowest point, and take a horizontal measurement of the hip circumference at its widest point.

For both: Measure the circumference of the neck starting just below the larynx (Adam's apple), with the tape slightly angled down toward the front. Keep the neck relaxed and avoid protruding it outward.

Once you have gathered these precise measurements, you can plug them into the formulas below to calculate your body fat percentage. We have provided both the United States Customary (USC) and Metric System equations:

Male body fat percentage (BFP) formula

USC Units

$$BFP = 86.010 × log_{10}(abdomen-neck) - 70.041 × log_{10}(height) + 36.76$$

Metric Units

$$BFP = \frac{495}{1.0324 - 0.19077 × log_{10}(waist-neck)) + 0.15456 × log_{10}(height)} - 450$$

Female body fat percentage (BFP) formula

USC Units

$$BFP = 163.205 × log_{10}(waist+hip-neck) - 97.684 × (log_{10}(height)) - 78.387$$

Metric Units

$$BFP = \frac{495}{1.29579 - 0.35004 × log_{10}(waist+hip-neck) + 0.22100 × log_{10}(height)} - 450$$

Please note that the results from these equations are well-educated estimates. Because they are designed to be as universal as possible, they rely on certain physiological assumptions. For a highly accurate, clinical assessment of your body fat content, scientists and medical professionals typically use hydrostatic weighing (underwater density testing), DEXA scans, or bioelectrical impedance analysis (BIA).

The equation for Fat mass (FM)

$$Fat\ Mass = Body\ Fat × Weight$$

The equation for Lean Mass (LM)

$$Lean\ Mass = Weight - Fat\ Mass$$

BMI Approach

The Body Mass Index (BMI) offers another reliable way to estimate your body fat percentage. The BMI method uses an individual’s age, height, and weight to calculate an estimated body fat ratio. Below are the standard equations used to calculate a user’s body fat percentage based on their BMI.

If you need to establish your baseline metric first, use a dedicated BMI Calculator to find your exact BMI, alongside detailed information regarding its clinical significance, health categories, and methodological limitations.

Adult Male Body fat percentage (BFP) equation

$$BFP = 1.20 × BMI + 0.23 × Age - 16.2$$

Adult Female Body fat percentage (BFP) equation

$$BFP = 1.20 × BMI + 0.23 × Age - 5.4$$

Boys’ Body fat percentage (BFP) equation

$$BFP = 1.51 × BMI - 0.70 × Age - 2.2$$

Girls’ Body fat percentage (BFP) equation

$$BFP = 1.51 × BMI - 0.70 × Age + 1.4$$