Short answer
Hamwi: men 106 lb for 5 ft plus 6 lb per extra inch, women 100 lb plus 5 lb per inch; subtract 10% for a small frame, add 10% for a large one. A man 5′10″ is 166 lb (149.4–182.6 lb); a woman 5′5″ is 125 lb (112.5–137.5 lb).
1. The Hamwi formula
- Men: 106 lb for the first 5 ft, plus 6 lb for each extra inch.
- Women: 100 lb for the first 5 ft, plus 5 lb for each extra inch.
2. The frame adjustment
The result is treated as the medium-frame value. A common rule of thumb subtracts 10% for a small frame and adds 10% for a large frame.
3. Reference values by height
| Height | Small (−10%) | Medium | Large (+10%) |
|---|---|---|---|
| Man, 5′4″ | 117 lb | 130 lb | 143 lb |
| Man, 5′8″ | 138.6 lb | 154 lb | 169.4 lb |
| Man, 5′10″ | 149.4 lb | 166 lb | 182.6 lb |
| Man, 6′0″ | 160.2 lb | 178 lb | 195.8 lb |
| Woman, 5′0″ | 90 lb | 100 lb | 110 lb |
| Woman, 5′4″ | 108 lb | 120 lb | 132 lb |
| Woman, 5′6″ | 117 lb | 130 lb | 143 lb |
| Woman, 5′8″ | 126 lb | 140 lb | 154 lb |
4. Worked example
A woman 5′5″: 100 + 5 × 5 = 125 lb (56.7 kg) for a medium frame. Small is 112.5 lb (51.0 kg) and large is 137.5 lb (62.4 kg).
5. Keep it in perspective
Hamwi dates from 1964 and is a simple reference point. It ignores muscle, age and body composition, so treat it as a starting point rather than a target.
6. Frequently asked questions
How do I calculate ideal weight with the Hamwi formula?expand_more
Men: 106 lb plus 6 lb per inch over 5 ft. Women: 100 lb plus 5 lb per inch over 5 ft.
How much does frame size change ideal weight?expand_more
A common adjustment is about 10% lower for a small frame and 10% higher for a large frame.
Is the Hamwi formula accurate?expand_more
It is a simple reference formula from 1964. It does not account for muscle, age or body composition.
Does frame size change my healthy BMI range?expand_more
No. BMI categories use height and weight only; frame size is extra context some ideal-weight methods use.