Body Composition Calculators

Body composition refers to the percentages of fat, bone, water, and muscle in your body. Unlike weight alone, body composition gives you a more complete picture of your health by distinguishing between fat mass and lean mass.

Start with BMI for a quick screening of your weight relative to height. For a more detailed picture, use the Body Fat Calculator (Navy method) or the Army Body Fat Calculator. The Ideal Weight Calculator compares four clinical formulas, while the Lean Body Mass and Waist-to-Hip Ratio calculators offer additional health insights.

Monthly measurements are ideal for tracking progress without obsessing over daily fluctuations. Measure under consistent conditions — same time of day, same hydration level, and same clothing — for the most reliable comparisons.

BMI is a useful screening tool but has limitations. It does not distinguish between fat and muscle mass, so athletes or muscular individuals may have a high BMI despite being healthy. Combining BMI with body fat percentage or waist-to-hip ratio gives a more accurate assessment.

Online calculators use clinically validated formulas (like the Navy tape test or Boer formula) and provide reliable estimates for most people. However, they are not a substitute for professional body composition tests such as DEXA scans or hydrostatic weighing.