BMI & Body Fat Estimation Calculator
Calculate your Body Mass Index (BMI) and get an estimation of your Body Fat percentage based on standard formulas.
Body Mass Index (BMI) is a common metric used to categorize weight relative to height. However, for people who lift weights, BMI is often flawed because it cannot distinguish between fat and muscle.
This calculator provides your standard BMI, but also includes a formula-based Body Fat estimation (using the US Navy formula) for a more accurate picture of your body composition.
BMI & Body Fat Calculator
BMI
Est. Body Fat
Sources and Limitations
BMI Formula: Weight (kg) / Height (m)² Developed by Adolphe Quetelet in the 19th century. It is a population-level metric and does not account for muscle mass, making it misleading for strength athletes.
US Navy Body Fat Formula: Developed by the Naval Health Research Center. It uses tape measurements to estimate body density and body fat percentage. Source: Hodgdon, J. A., & Beckett, M. B. (1984). Technique for measuring body circumferences and skinfold thicknesses to estimate body fat.
Caution: Tape measure formulas are estimates with a margin of error (often ±3-5%). For highly accurate results, a DEXA scan or hydrostatic weighing is required.
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