Ideal Weight Calculator
Compare ideal body weight estimates from the Devine, Robinson, Miller and Hamwi formulas, alongside a BMI-based healthy range.
Average ideal weight
70 kg
154.4 lb · 11 stone
Healthy BMI range
56.7 – 76.3 kg
Devine formula
70.5 kg
- Devine (1974)
- 70.5 kg
- Robinson (1983)
- 68.9 kg
- Miller (1983)
- 68.7 kg
- Hamwi (1964)
- 72 kg
- BMI-based healthy range
- 56.7 – 76.3 kg
- Height in feet and inches
- 5 ft 8.9 in
How this was calculated
- 1.Height = 68.9 inches, which is 8.9 inches over 5 ft.
- 2.Devine: 50 kg + 2.3 × 8.9 = 70.5 kg.
- 3.The four formulas differ in their constants, which is why they disagree by a few kilograms.
- 4.A BMI of 18.5–24.9 at 1.75 m corresponds to 56.7–76.3 kg.
Ideal-weight formulas were designed for drug dosing, not aesthetics. A healthy weight is a range, and muscle mass, frame size and age all shift it.
How the ideal weight calculation works
These formulas estimate a weight associated with lowest mortality for a given height. Devine's, from 1974, is still used in medicine for calculating drug doses; Robinson, Miller and Hamwi are refinements with slightly different constants.
All four were derived from population data decades ago and none accounts for body composition. A muscular person can be healthy well above the estimate; someone with low muscle mass can be unhealthy within it.
Treat the output as a reference point. The BMI-based range is usually more useful because it describes a band rather than a single number.
Worked example
A man of 180 cm.
- →180 cm = 70.9 inches
- →9.1 inches over 5 ft
- →Devine: 50 + 2.3 × 9.1 = 70.9 kg
Answer: Around 71–76 kg depending on the formula, with a BMI-healthy range of 60–81 kg.
Ideal Weight FAQs
Which formula should I trust?
None is definitive. The average of the four is a reasonable centre, and the BMI range is a better guide for most people.
Does frame size matter?
Yes. Wrist circumference and shoulder width affect healthy weight, which these formulas ignore, so a naturally broad frame can be healthy above the estimate.
Is ideal weight the same as goal weight?
Not necessarily. Body composition, fitness and how you feel matter more than hitting a number derived from height alone.
Ideal Weight Calculator is part of the health calculators collection on Calcora, alongside 7 other tools. Results are calculated in your browser and are for information only — see our disclaimer.
You might also like
More tools from the same collection, picked for what people usually calculate next.