Use our Fat Free Body Weight Calculator to estimate how much of your total body weight comes from muscle, bone, water and other non-fat tissues. Simply enter your weight and body fat percentage to get an instant result.
Enter your weight and estimated body fat percentage.
Estimated weight excluding body fat
Fat-free body weight is the estimated portion of your total body weight that does not consist of stored body fat. It includes muscle, bones, organs, body water, connective tissue and other non-fat components of the body.
Looking only at scale weight does not show how much of your body is fat or lean tissue. Two people can weigh exactly the same while having very different body compositions. A fat free body weight calculator helps provide additional context by estimating how much of your weight remains after body fat is removed from the calculation.
The calculator is designed to stay quick and easy to use. You only need two measurements: your current body weight and your estimated body fat percentage. Choose Metric for kilograms or US for pounds, enter your measurements, and select the calculate button. Your estimated fat-free body weight will appear immediately along with your fat mass and lean percentage.
Add your current body weight in kilograms or pounds.
Enter your best available body fat percentage estimate.
See estimated lean body weight and fat mass instantly.
Fat-free body weight is calculated by removing the estimated amount of body fat from total body weight. This makes the formula straightforward as long as you have a reasonable estimate of your body fat percentage.
For example, someone who weighs 80 kg and has an estimated body fat percentage of 20% would have approximately 64 kg of fat-free body weight. Their estimated fat mass would be 16 kg.
Total body weight represents everything in your body, including fat, muscle, water, bone and other tissue. Fat-free body weight removes estimated body fat from that total. This distinction can be useful because a change on the scale does not automatically tell you whether you gained or lost fat, muscle or water.
Includes both fat and lean tissue. It is easy to measure but does not explain what your body weight consists of.
Excludes estimated fat mass. It provides additional body-composition information when used with a reasonably accurate body fat estimate.
Your body fat percentage has a direct effect on your fat-free body weight result. If your body fat estimate is lower than your actual percentage, the calculator will estimate more fat-free mass. If the body fat estimate is too high, the calculated fat-free weight will be lower.
Smart scales, skinfold calipers, body circumference formulas, bioelectrical impedance devices and professional scans can all produce slightly different results. For progress tracking, it is usually better to use the same measurement method under similar conditions instead of frequently switching between different methods.
Estimating fat-free body weight may be helpful when monitoring changes in body composition. During a weight-loss program, for example, the scale may decrease because of changes in body fat, water or lean tissue. Tracking fat-free weight alongside total body weight can provide more context about what may be changing.
People who strength train may also use fat-free body weight as one way to monitor long-term body-composition progress. Someone may remain close to the same scale weight while gradually gaining muscle and reducing body fat. In that case, total weight alone would not show the full change.
Resistance training, adequate protein intake, balanced nutrition, sufficient energy, good sleep and recovery can all contribute to maintaining healthy lean tissue. Individual needs vary depending on age, activity level, health status and fitness goals.
Fat-free body weight should therefore be viewed as one useful number rather than a complete measure of health. Strength, cardiovascular fitness, mobility, waist measurements, nutrition and overall wellbeing are also important when evaluating progress.
The terms are often used similarly in general fitness calculations. Both broadly describe body weight excluding stored body fat, although technical definitions can vary depending on the body-composition model being used.
No. If you already know your estimated body fat percentage, the basic fat-free body weight calculation only requires your total body weight and body fat percentage.
Yes. This calculator works with both kilograms and pounds. Simply select US units before entering your weight.
The mathematical formula is straightforward, but the accuracy of the result depends largely on the accuracy of your body fat percentage measurement.
It can provide useful information about body-composition trends, especially when the same body fat measurement method is used consistently over time.
No. Healthy body composition varies according to height, age, sex, genetics, activity level and medical factors. Fat-free weight should not be treated as a single health target.
