Ideal Weight Calculator (4 Formulas)
Enter your height and sex, and this calculator applies four widely cited ideal-body-weight formulas — Devine, Robinson, Miller, and Hamwi — and shows the spread between them as a range rather than a single figure. It also overlays the weight band that corresponds to a healthy BMI for your height. These are population-level formulas from the 1960s–1980s, built to guide drug dosing and quick clinical estimates, not personalized targets: they ignore your muscle mass, frame size, age, and body composition. Treat the output as a rough reference range, not a goal.
Dated, population-level formulas that take only height and sex. They ignore muscle mass, frame, and age, and are not medical advice.
Ideal weight range
71.5–77.3kg
Spread across four formulas — a range, not a single target.
The four formulas & BMI band
| Devine (1974) | 75.0 kg |
| Robinson (1983) | 72.7 kg |
| Miller (1983) | 71.5 kg |
| Hamwi (1964) | 77.3 kg |
| Healthy-BMI band | 59.9–80.7 kg |
Estimate by formula
Population formulas, not personalized — not medical advice.
Compare scenarios
Run the same calculation with two or three input sets side by side. Differences are highlighted; every number comes from the same tested formula as the calculator above.
| Input | Scenario A | Scenario B |
|---|---|---|
| Sex | ||
| Height Cm |
How it works
Every one of the four formulas shares the same skeleton: a base weight defined at 5 feet of height, plus a fixed amount added for each inch above 5 feet. The calculator first converts your height to inches (height in cm ÷ 2.54), subtracts 60 inches to get the inches over 5 feet, and floors that at zero so heights below 5 feet simply return the base weight. It then plugs that number into each formula with that formula's own base and per-inch coefficient.
The four formulas use different constants because they were fitted to different data. For men the per-inch increment is 2.3 kg (Devine), 1.9 kg (Robinson), 1.41 kg (Miller), or 2.7 kg (Hamwi); women use slightly lower bases and increments. Because the coefficients differ, the four estimates rarely agree — which is exactly why this tool reports the lowest and highest as a band instead of pretending there is one right answer. The width of that band is itself a reminder of how approximate these formulas are.
As a cross-check, the calculator also draws the weight range for a healthy Body Mass Index at your height, computed as 18.5 and 24.9 multiplied by your height in metres squared. BMI and the ideal-weight formulas measure different things and were derived separately, so they will not line up exactly. Where the formula range sits inside the BMI band, the estimates broadly agree; where it does not, that gap is a signal to rely on measured body composition and professional judgement rather than any single equation.
Frequently asked questions
Which of the four formulas is the 'right' one?+
None of them is authoritative — that is the point of showing all four as a range. The Devine formula (1974) is the most widely used, largely because it became the default for weight-based drug dosing, but it was never validated as a health target. Robinson and Miller (both 1983) were later refits of the same idea to different reference populations, and Hamwi (1964) is the oldest and tends to run highest for tall people. When they disagree, the honest answer is that the true 'ideal' is uncertain, so we present the spread instead of picking a winner.
Why doesn't the result account for my muscle or build?+
It can't. All four formulas take only height and sex as inputs, so a muscular athlete and a sedentary person of the same height and sex get the identical estimate even though their healthy weights differ substantially. Muscle is denser than fat, so lean, well-trained people routinely sit above these ranges while being perfectly healthy. The formulas also ignore frame size, age, and fat distribution. Read the number as a crude population average for your height, not a personalized target, and use a body-composition measurement if you need something specific to you.
Is this medical advice or a weight-loss goal?+
No. This is an educational reference calculator, not medical, nutritional, or clinical advice, and the ranges it produces are not weight-loss goals. The formulas are dated, population-level tools that do not consider your individual health, and the BMI cross-check has well-known limitations of its own. Before setting any target weight or making changes to your diet, exercise, or medication, talk to a doctor or registered dietitian who can assess your full situation.