Ideal weight
calculator
Four medical formulas, four slightly different answers, that spread is the honest truth about 'ideal weight.' Enter your height and see all of them, plus the healthy-BMI band.
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Where "ideal weight" formulas come from
These equations were built for medicine, not aesthetics, the best-known, Devine (1974), was created for drug dosing. Each takes a base weight at 5 feet and adds a fixed amount per inch above it, which is why they only need height and sex.
Why four answers
Robinson and Miller re-fitted the idea in 1983 with different slopes; Hamwi's 1964 rule came first as a bedside shortcut. At most heights they cluster within a few kilograms, the spread is a feature, honestly showing that "ideal" is a band, not a point.
Reading it sensibly
None of these formulas see muscle, frame or body composition, an athletic person can sit "over" every formula while being in excellent shape. The healthy-BMI band shown alongside is the broader population reference; body fat percentage says far more about composition than any height-based number. Use these as reference points, not verdicts.
Ideal weight FAQ
The 1974 formula behind most 'ideal body weight' references: 50 kg (men) or 45.5 kg (women) plus 2.3 kg per inch of height above 5 feet. It was originally designed for calculating medication doses.
Each was fitted differently, Hamwi (1964) as a quick clinical rule, Devine (1974) for dosing, Robinson and Miller (1983) as statistical refits. The few-kilogram spread reflects genuine uncertainty in the concept.
Not exactly. The formulas give single reference points; health guidance uses ranges like BMI 18.5–24.9, shown above, and composition matters more than either, muscle and fat weigh the same on a scale.
Not from this alone. The formulas ignore muscle and frame entirely. Look at body fat percentage, waist measurements and health markers with a professional before drawing conclusions.