Ideal Weight Calculator
Estimate a healthy target weight for your height and sex using several established formulas.
Last reviewed July 1, 2026
“Ideal weight” formulas give a rough target based on height and sex only — they ignore build, muscle, and age. Treat the healthy BMI range as the more meaningful guide. Not medical advice.
How much should you weigh? There's no single answer, but several well-known formulas estimate an 'ideal' weight from your height and sex. This calculator shows the results of the Devine, Robinson, Miller and Hamwi formulas side by side, plus the healthy weight range based on BMI.
Because the formulas disagree slightly, seeing them together gives you a sensible range rather than one arbitrary number.
The Ideal Weight formula
Devine — Men: 50 kg + 2.3 × (inches over 5 ft); Women: 45.5 kg + 2.3 × (inches over 5 ft)inches over 5 ft = your height in inches minus 60. The Robinson, Miller and Hamwi formulas use the same structure with slightly different baselines and per-inch increments.
Worked example
A man 5 ft 10 in tall is 10 inches over 5 ft, so the Devine estimate is 50 + 2.3 × 10 = 73 kg (about 161 lb). The other formulas give figures a few kilograms either side.
Why there are several formulas
The Devine formula was created in the 1970s for medication dosing and is the most widely cited. Robinson, Miller and Hamwi are refinements that adjust the baseline and the per-inch increment. None is definitively 'correct' — that's why we show all four and their average.
All of them use only height and sex, so they can't account for your frame size, muscle mass, or age. A muscular athlete may sit above their 'ideal' weight and still be perfectly healthy.
A better guide: the healthy BMI range
Rather than a single target, aim for the healthy weight range for your height (a BMI between 18.5 and 24.9), which this calculator shows. A range is more realistic and forgiving than one exact number, and it's what most health guidelines actually use.
Frequently asked questions
▶What is my ideal weight?
Enter your height and sex above to see estimates from four formulas and a healthy weight range. There's no single 'ideal' — a range based on BMI is the most useful target.
▶Are ideal weight formulas accurate?
They're rough guides based on height and sex only. They ignore muscle, frame and age, so treat them as a ballpark and use the healthy BMI range as the more meaningful measure.
▶What is the Devine formula for ideal body weight?
For men it's 50 kg plus 2.3 kg for every inch of height over 5 feet; for women, 45.5 kg plus 2.3 kg per inch over 5 feet. It was originally devised in the 1970s for medication dosing.
▶Which ideal weight formula should I use?
There's no single 'right' one — Devine, Robinson, Miller and Hamwi disagree slightly. Viewing all four gives a sensible range, and the healthy BMI range is the more meaningful target.
▶Does ideal weight account for muscle or frame size?
No. These formulas use only height and sex, so a muscular or large-framed person may sit above their 'ideal' figure while being perfectly healthy. Body fat percentage is a better individual measure.
▶Is ideal weight the same for men and women?
No. For the same height, the formulas give women a lower baseline than men, reflecting differences in average body composition.
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Open calculator →Disclaimer: Ideal Weight Calculator results are estimates for general information and education only, and are not financial, tax, legal or medical advice. Verify important decisions with a qualified professional.