What is Body Fat Percentage?

A person's body fat percentage is the total weight of the person's fat divided by the person's weight and consists of essential body fat and storage body fat.

Essential body fat is necessary to maintain life and reproductive functions. The percentage for women is greater than that for men, due to the demands of childbearing and other hormonal functions. Essential fat is 3–5% in men, and 8–12% in women.

Storage body fat consists of fat accumulation in adipose tissue, part of which protects internal organs in the chest and abdomen. The minimum recommended total body fat percentage exceeds the essential fat percentage value reported above. A number of online tools are available for calculating estimated body fat percentage.

Some regard the body fat percentage as the better measure of an individual's fitness level, as it is the only body measurement which directly calculates the particular individual's body composition without regard to the individual's height or weight.

The widely-used body mass index (BMI), on the other hand, simply makes blanket assumptions as to what every individual of a certain height should ideally weigh, regardless of the body composition which makes up that weight. The BMI gives particularly inaccurate information with regard to individuals with above-average lean muscle mass, classifying such individuals as "overweight" or "obese" despite the fact that their body fat percentage would indicate they are in excellent physical condition.