Calculate your ideal body weight using the Hamwi formula (1964). The oldest major IBW equation, widely used in clinical dietetics with the highest per-inch weight increment.
The Hamwi formula is a historical ideal body weight equation that is still reproduced in clinical references. It uses a sex-specific base weight at 5'0" and then adds a fixed increment for each additional inch of height.
Because the formula adds more weight per inch than some later equations, it tends to produce higher estimates for taller people and lower estimates for shorter people. That makes it useful as one reference point, but not a definitive weight target.
Hamwi is one of several historical ideal-body-weight equations that may still appear in clinical materials. For taller individuals, it often gives higher estimates than some later formulas, so it is best treated as one reference among several rather than a target to chase.
Men: IBW = 48.0 + 2.7 × (height in inches − 60) Women: IBW = 45.5 + 2.2 × (height in inches − 60) Result in kg. Frame adjustments: Small frame: IBW − 10% Large frame: IBW + 10%
Result: IBW: 75.0 kg (165 lbs) | Small frame: 67.5 kg | Large frame: 82.5 kg
Male at 5'10" (70 inches): IBW = 48.0 + 2.7 × (70 − 60) = 48.0 + 27.0 = 75.0 kg (165 lbs). For a small frame (−10%): 67.5 kg. For a large frame (+10%): 82.5 kg. Hamwi produces a higher estimate than some later formulas at this height.
Wrist circumference is a simple proxy for frame size. Measure at the narrowest point, just distal to the wrist bones, and compare the result with published height-based tables. Frame-size categories used with Hamwi come from historical anthropometric references rather than direct outcome studies.
Hamwi is one of several historical ideal-body-weight equations that were developed before modern body-composition tools were widely available. Newer formulas are often used today, but Hamwi remains a common reference because it is simple and easy to compare against other equations.
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This calculator applies the standard Hamwi height-based equation and optionally shows the common ±10% frame-size adjustment used alongside the formula. The result is presented as a reference weight, not as a clinical target or a measure of health.
When the page compares Hamwi against other ideal-body-weight equations, the comparisons are descriptive only. Different formulas use different assumptions, so the values can legitimately differ by several kilograms without any one formula being objectively “correct.”
Hamwi is commonly reproduced in dietetic references because it is a simple historical equation with an optional frame-size adjustment. Its higher per-inch increment can make it a useful comparison point, but it should not be treated as more accurate than other ideal-body-weight equations.
Hamwi uses a higher per-inch increment than some later equations, so it can rank lower at shorter heights and higher at taller heights. That crossover behavior is one reason it is best used as a comparison reference, not as a universal standard.
Body frame size is an anthropometric estimate of skeletal build, usually approximated with wrist circumference or elbow breadth. It is a rough way to contextualize ideal-body-weight formulas, not a direct measure of health.
Hamwi is a historical formula that is still reproduced in clinical references. It is useful as a comparison point, but it was not built from modern outcome-based validation.
Not necessarily. Being 10–20% above any IBW formula is common and often compatible with good health, especially if you carry more muscle mass than average.
No. Hamwi was designed for adults. Children and adolescents should be assessed with age- and sex-specific growth charts.