Body Fat Index Calculator

Calculate Your Health with the Body Fact Index (BFI)

Body fat percentage plays a vital role in overall health. Percentages that are too high or too low increase your risk of developing and worsening health conditions. DID YOU KNOW that excess body fat is linked to type 2 diabetes, heart disease, high blood pressure, sleep apnea, kidney disease, stroke, various cancers, and a growing list of health conditions? Discovering your individual body fat percentage is the first step in taking control of your health. Unfortunately in the past, attaining accurate body fat percentages has not been easy or convenient. The Body Mass Index (BMI), average scales, and hand-held devices do not accurately estimate body fat percentages. Fortunately, the BFI is available to offer quick, easy, and accurate results. The Dexa Scan (Dual-Energy X-ray Absorptiometry) is the gold standard for measuring body fat, muscle, and bone density. Although the Dexa Scan is the leader for estimating body fat percentage, due to radiation exposure, testing cannot be repeated on a regular basis. Within two-percent accuracy of the Dexa Scan, the BFI offers the safest and most reliable means for determining your body fat percentage. Simply enter your gender, age, height, weight, ethnicity, waist measurement, and fitness routines or the lack thereof. To get started on calculating your body fat percentage, complete the form below:


The Lie Accepted Around the World

Imagine being told you are overweight or obese, then discovering that you really are not! What if your doctor said you are at a healthy weight, then you find out that you are TOFI (Thin-Outside-Fat-Inside)? How can this be? As doctors and leading medical and health organizations continue to promote the use of the BMI to classify a person’s health, people will continue to receive inaccurate results.

The one-size-fits-all approach of the BMI is flawed. The BMI does not consider a number of important factors. Therefore, it isn’t a true reflection of body fat or health. According to researchers from the University of California, Los Angeles (UCLA), thousands —if not millions— of people have been inaccurately deemed overweight or obese. This study, published in the International Journal of Obesity, revealed the ineffectiveness of the BMI and suggested that doctors and patients turn to alternative methods to accurately assess healthy weight ranges.

In this study reported in the International Journal of Obesity, it became apparent that 54 million Americans are misclassified as overweight and obese according to the BMI, while based upon cardio-metabolic measures, they are all in perfect health. In the same report, 21 million people categorized as normal by BMI standards have excess fat with an increased risk for various diseases.

Another study reported by the National Institutes of Health (which is credited for helping to popularize the BMI), clearly states that the BMI has misclassified the relationship between weight and health. In this particular study of nearly 1,000 people using the BMI, approximately 36%-43% fell into the category of obese. In contrast to the BMI results, according to Dexa Scan (Dual-Energy X-ray Absorptiometry), 80 percent of these people were actually considered to be obese.

BMI Back Story

The BMI, as we know it today, was created in the 1830s by Lambert Adolphe Jacques Quetelet (1796-1874), a Belgian mathematician, sociologist, statistician and astronomer. Thus, the BMI was originally referenced as the Quetelet Index.

In the 1950s, the BMI was reinvented by Ancel Keys, an American physiologist and nutritionist who studied the influence of diet on health. Years later, Ancel Keys published a paper in the July 1972 edition of the Journal of Chronic Diseases featuring the BMI as a means to estimate one’s health risks based on height and weight.

In 1985, the National Institutes of Health popularized the credibility and use of the BMI. Today, it continues to be the most widely used method for determining whether a person is overweight, over-fat, healthy or obese.

Promoting Wrong Over What’s Right

Why do universities, physicians, and leading institutions like the World Health Organization, Centers for Disease Control and Prevention, and National Institutes of Health continue to promote the BMI when they know (often times admit publicly) it isn’t accurate? Why not create a new method that replaces the inaccuracies of the BMI?
The reality is that the BMI is an inexpensive, easy method to use for clinicians and the general public. It has been used for many years and continues to serve as the basis for many studies and research projects. To top it off, ceasing the use of the BMI would disrupt and discredit many published studies.

The good news is that there is an accurate alternative to the BMI. After years of studies, research, and the development of a proprietary algorithm, we now have the BFI. Within two-percent accuracy of the Dexa Scan, the BFI can estimate your body fat percentage.

Why the Body Fact Index (BFI)?

After it became apparent that the BMI was inaccurate for measuring body fat, Stayhealthy, Inc. began the process of developing the BFI. With the BFI conveniently accessible online and through mobile applications on Smart Phones and digital devices such as iPads and tablets, accurately measuring and tracking body fat percentages has never been easier.

In 1998, Stayhealthy, Inc. acquired the rights to bio-impedance technology that was used to predict one’s lean mass, fat mass, and body water. Shortly after Stayhealthy acquired these rights, a clinical study was initiated at East Tennessee State University to test the accuracy of bio-impedance technology when compared to hydrostatic weighing. At this time, hydrostatic weighing had been considered the gold standard for determining one’s body fat percentage. After this comparison proved that the bio-impedance technology was not accurate, equations were adjusted and a new study completed. With time and a consistent effort to improve the accuracy of the equations, the results were finally as good as hydrostatic weighing. After these findings, Stayhealthy developed a hand-held device that accurately measured body fat, hydration, and lean mass. Stayhealthy applied for under 510K through the Food and Drug Administration (FDA). After the FDA cleared the device, it was released.

In the early 2000’s, Stayhealthy conducted a further study comparing their results to Dexa Scan, which was and is the gold standard for estimating body fat percentage. Once more, equations were tweaked for accuracy and the FDA cleared the changes. In 2018, after Stayhealthy commenced a further study using 25,000 Dexa Scans, equations were developed for use on a smart phone. The BFI Calculator and BFI mobile app were created from the outcomes of this enhanced algorithm.

Accuracy Means Clarity

According to the BMI, professional athletes such as tennis player Serena Williams and baseball player Prince Fielder are classified as overweight or obese. Even Hollywood actors Tom Cruise and Arnold Schwarzenegger find themselves in the same category. With many people being inappropriately categorized by the BMI, it is time for a change!

The BFI technology makes it possible to easily, affordably, and accurately estimate your body fat percentage. This knowledge affords everyone the opportunity to reduce excess body fat and improve overall health.
To understand what your body fat percentage means, see the chart below. No matter your current results, you can begin to improve your body composition and overall health immediately!


HealthStatus has been operating since 1998 providing the best interactive health tools on the Internet, millions of visitors have used our health risk assessment, body fat and calories burned calculators. The HealthStatus editorial team has continued that commitment to excellence by providing our visitors with easy to understand high quality health content for many years.

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Written by HealthStatus
Medical Writer & Editor

HealthStatus has been operating since 1998 providing the best interactive health tools on the Internet, millions of visitors have used our health risk assessment, body fat and calories burned calculators. The HealthStatus editorial team has continued that commitment to excellence by providing our visitors with easy to understand high quality health content for many years.

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