Health & Fitness / Measure the body.
Body Composition
BMI, body-fat % (Navy method), lean body mass, ideal weight, waist-to-hip ratio, and water-intake math that powers the r/loseit, r/Fitness, and r/GainIt body-composition threads.
5 tools available
BMI Calculator
Calculate Body Mass Index and see healthy ranges.
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Daily Water Intake Calculator
Get a personalized daily water target based on weight, activity, and climate.
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Body Fat % Calculator (Navy Method)
Estimate body-fat percentage from tape measurements and BMI.
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Ideal Weight Calculator (Devine / Hamwi / Robinson)
Compare the popular clinical ideal-weight formulas.
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Waist-to-Hip Ratio Calculator
Compute waist-to-hip ratio and the WHO health-risk band.
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