Ideal Weight Calculator
Estimate ideal body weight (IBW) from height and sex using four well-known formulas side-by-side, plus the healthy BMI weight range.
How it works
- 1
Enter your values in the fields.
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Results update automatically as you type.
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Use Reset to clear and try another scenario.
Why use this calculator
- Robinson, Miller, Devine & Hamwi formulas compared
- Healthy BMI weight range included
- Fast height-based estimate
- Not a medical target
About ideal weight formulas
There is no single 'correct' formula for ideal body weight — Robinson (1983), Miller (1983), Devine (1974), and Hamwi (1964) were all developed mainly to estimate medication dosing, using height and sex as inputs. They usually agree within a few kilograms of each other. This calculator shows all four side-by-side, plus the weight range that corresponds to a healthy BMI (18.5–25) at your height, so you can compare references instead of relying on one number.
Formulas for finding the ideal weight
All four formulas share the same shape: a base weight at 5 feet (152 cm), plus a fixed amount added per inch of height above that. For example, a 5'10" (178 cm) male using the Devine formula adds 2.3 kg × 10 inches to 50 kg, for about 73 kg (161 lb).
| Formula | Male | Female |
|---|---|---|
| Hamwi (1964) | 48.0 kg + 2.7 kg / inch over 5 ft | 45.5 kg + 2.2 kg / inch over 5 ft |
| Devine (1974) | 50.0 kg + 2.3 kg / inch over 5 ft | 45.5 kg + 2.3 kg / inch over 5 ft |
| Robinson (1983) | 52.0 kg + 1.9 kg / inch over 5 ft | 49.0 kg + 1.7 kg / inch over 5 ft |
| Miller (1983) | 56.2 kg + 1.41 kg / inch over 5 ft | 53.1 kg + 1.36 kg / inch over 5 ft |
How to use the range
Treat every value here as a population-level reference, not a personal target. Age, body frame, muscle mass, and overall health matter more than hitting an exact number — a fit, muscular person can weigh more than any of these formulas suggest and still be perfectly healthy.
Limitations
These formulas only factor in height and sex. They don't account for body frame size, muscle-to-fat ratio, activity level, or health conditions — so a lean athlete can be well above every number here and still be perfectly healthy. They also apply to adults; children and teens are better assessed with pediatric growth charts from a doctor.
Frequently asked questions
Which formula should I trust?
None is definitively more 'correct' — Devine is the most widely used in medicine, but Robinson and Miller are later refinements. Comparing all four (and the healthy BMI range) gives a more honest picture than a single number.
Should I aim exactly for this number?
Not necessarily. Healthy weight depends on many factors these formulas ignore, including muscle mass and body composition.
Does muscle mass matter?
Yes. All four formulas only use height and sex, so athletes and muscular individuals often weigh more than these estimates suggest while remaining healthy.