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Health & body · Reference

Ideal weight
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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.

Devine · Robinson · moreBMI range tooNo sign-up
Reference weightsfour formulas
cm
Robinson (1983)widely used clinically
Miller (1983)gentler slope with height
Hamwi (1964)the original quick rule
Healthy BMI rangeBMI 18.5–24.9 at your height

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.

Devine
men: 50 + 2.3·in over 5ft · women: 45.5 + 2.3·in

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.

Common questions

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.