Ideal Weight Calculator
See the WHO healthy weight range for your height, alongside what the Devine, Robinson, Miller and Hamwi formulas report.
Result
Enter height to see the result.
https://calcgallery.com/body-composition/ideal-weight-calculator/
How to use the Ideal Weight Calculator
- Choose which published equation to apply. The source studies used a female/male binary.
- Enter your height in feet and inches or in centimetres.
- Read the healthy weight range first. It is the figure with a population-health basis behind it.
- Compare the four formulas below it, and read what they were published for.
How it is calculated
Two different things are shown on this page, and they do not have equal standing.
The healthy weight range comes from reversing the BMI formula against the WHO band for normal weight:
lower = 18.5 × height (m)²upper = 24.9 × height (m)²That band was set from large epidemiological studies relating BMI to health outcomes across populations. It is wide, it is a population statistic rather than a personal target, and it carries every limitation BMI carries — but there is published evidence underneath it.
The four formulas each start from a base weight at five feet and add a fixed amount per inch above that:
| Formula | Year | Male | Female |
|---|---|---|---|
| Devine | 1974 | 50.0 + 2.3 per inch | 45.5 + 2.3 per inch |
| Robinson | 1983 | 52.0 + 1.9 per inch | 49.0 + 1.7 per inch |
| Miller | 1983 | 56.2 + 1.41 per inch | 53.1 + 1.36 per inch |
| Hamwi | 1964 | 48.0 + 2.7 per inch | 45.5 + 2.2 per inch |
All four are in kilograms with height in inches. Because they share a shape but not their numbers, they agree near five feet and fan out with height.
Below five feet they stop being supported. The increment term goes negative, so each formula returns less than its base weight by extrapolating outside the range of heights it was fitted on. The calculator still shows the numbers, and says on the results panel that this is what is happening, rather than presenting an extrapolation as if it were a result.
Practical tips
Read the range, not the four numbers. The band is the part of this page with evidence behind it. The formulas are shown because people search for them and deserve to find out what they are, not because they are better answers.
A dosing formula is not a health target. Devine’s paper is about aminoglycoside pharmacokinetics. The fact that a number is published, old and widely quoted does not make it a statement about what anyone should weigh.
Frame and composition are invisible here. Two people of the same height and sex get identical numbers no matter how differently they are built. If body composition is what you care about, a body fat or lean mass estimate says more than any weight target can.
The range is deliberately wide. At five foot ten it spans roughly twenty kilograms. That width is not vagueness; it reflects how weakly weight alone predicts health outcomes for an individual.
Where you sit within the band is a clinical conversation. A calculator can reverse an equation. It cannot weigh your history, your blood work or your circumstances, and it should not pretend to.
With your numbers
- Devine starts at 110.2 lb for five feet and adds 2.3 kg for each of the 10 inches above it, giving 160.9 lb
- Robinson 156.5 lb, Miller 155 lb and Hamwi 165.3 lb use the same shape with different numbers
- At 70 in, BMI 18.5 to 24.9 is 128.9 lb to 173.5 lb
Quick reference
There is no single ideal weight. The four formulas were published to scale drug doses, not to set a personal target.
| Example | Healthy weight range, lower |
|---|---|
| Male, 5 ft 6 in | 114.6 lb |
| Male, 5 ft 10 in | 128.9 lb |
| Male, 6 ft 2 in | 144.1 lb |
| Female, 5 ft 0 in | 94.7 lb |
| Female, 5 ft 4 in | 107.8 lb |
| Female, 5 ft 8 in | 121.7 lb |
| Male, 180 cm | 59.9 kg |
| Female, 165 cm | 50.4 kg |
Where the numbers come from
The fixed figures this calculator relies on, and the published source each one was checked against. How the calculators are built and checked
2 sources
WHO Technical Report Series 894 (2000), Obesity: preventing and managing the global epidemic, Table 2.1, p. 9, https://iris.who.int/handle/10665/42330: underweight <18.50, normal range 18.50-24.99, preobese 25.00-29.99, obese class I 30.00-34.99, class II 35.00-39.99, class III ≥40.00.
Used for
- Upper boundary of the WHO underweight band.
WHO Technical Report Series 894 (2000), Obesity: preventing and managing the global epidemic, Table 2.1, p. 9, https://iris.who.int/handle/10665/42330: underweight <18.50, normal range 18.50-24.99, preobese 25.00-29.99, obese class I 30.00-34.99, class II 35.00-39.99, class III ≥40.00. The one-decimal edge is the one IOM/NRC, Weight Gain During Pregnancy (2009), Table S-1, p. 2, prints ("18.5-24.9 kg/m²"); health-shared.ts classifies below the next band's lower edge (25.0, 30.0), so both tables give the same band.
Used for
- Upper boundary of the WHO normal BMI band.
Common questions about the Ideal Weight Calculator
- Why do the four formulas disagree?
- They were fitted by different authors between 1964 and 1983 on different samples, each anchored at five feet with a different base weight and a different increment per inch. At six feet the gap between the highest and lowest is several kilograms. None of them is a correction of the others; they are four independent attempts at the same rough approximation.
- Is there one ideal weight for my height?
- No. Weight at a given height depends on frame size, muscle mass, bone density and body composition, and none of these formulas knows any of those. A range is the most that the evidence supports, which is why the WHO band is shown first and the four single numbers are shown as history rather than as a target.
- What were these formulas actually for?
- Drug dosing. Devine published his in 1974 to estimate the dose of gentamicin against lean body mass rather than total weight, because dosing a heavier person on total weight overshoots. Robinson, Miller and Hamwi followed the same clinical purpose. None was derived to tell a person what they should weigh, and using them that way is a repurposing their authors did not propose.
- What about frame size?
- These formulas ignore it entirely. Hamwi is sometimes used with a rule of thumb that adds or subtracts ten percent for large or small frames, but that adjustment has no better source than the formula it modifies. Two people of the same height with visibly different skeletal builds receive the same number here.
- Should I try to reach these numbers?
- That is a question for a clinician, not for a calculator. A number computed from your height alone knows nothing about your health, your history or your body composition. The healthy range is a wide band derived from population studies, and where you sit within it, or whether it applies to you at all, is individual.