Health Formula • Published on July 30, 2026 • Last updated August 09, 2026
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Height in inches (only the inches over 5 feet / 60 inches are used in the multiplier term)
Base weight constants (kg) for men under each named formula, representing the estimated weight at exactly 5 feet tall
Base weight constants (kg) for women under each named formula, representing the estimated weight at exactly 5 feet tall
There is no single, universally agreed-upon Ideal Body Weight (IBW) formula. Devine (1974), Robinson (1983), Miller (1983), and Hamwi (1964) are four separate, independently published clinical equations, each developed by different researchers using different population data, and each still in use today for different purposes (Devine, for example, is widely used in medical drug-dosage calculations).
All four share the same basic structure — a base weight at 5 feet tall, plus a fixed amount added per inch of height above that — but use different constants, so they produce different results for the same person. Comparing all four together, rather than presenting one as definitive, gives a more complete and honest picture of what "ideal weight" estimates actually represent: a range, not a single number.
None of the four is definitively "most accurate" for the general population — each was derived from different data sets for different original purposes. Devine remains the most widely used in clinical/medical dosing contexts, but Robinson and Miller are considered by some researchers to be better calibrated to more contemporary population data.
Ideal Body Weight formulas are designed to estimate a target reference weight from body frame characteristics alone, independent of a person's current weight — which is different from BMI, which uses current weight and height together to categorize an existing measurement.
Not directly — all four formulas use only height and sex. Frame size (small, medium, large) is sometimes applied as a separate adjustment on top of the base IBW estimate, and none of the four formulas account for unusually high muscle mass, which can make a genuinely healthy person appear "overweight" by IBW standards.
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