About the Ideal Weight Calculator
This calculator shows what four classic formulas say your ideal weight is for your height and sex: Devine, Robinson, Miller and Hamwi. It also gives their average and the weight range that keeps a BMI between 18.5 and 24.9. Enter your height in centimetres or in feet and inches, and choose kilograms or pounds for the answers. The formulas are old rules of thumb for adults of average frame, and they disagree with one another, which is why a range is shown. Below 5 feet the formulas are extended by setting the extra-height term to zero. Healthy weight also depends on muscle, age, frame and ethnicity. For general information only, not medical advice.
Updated September 2026
How to use the Ideal Weight Calculator
- 1Choose your sex.
- 2Enter your height in centimetres, or in feet and inches.
- 3Choose whether to show weights in kilograms or pounds.
- 4Read the four formula results, their average and the healthy BMI range.
- 5Press Copy result to keep the numbers.
Four classic formulas
All four formulas start from a base weight for 5 feet (60 inches) of height and add a fixed number of kilograms for each extra inch. Devine gives 50 kg plus 2.3 kg per inch for men and 45.5 kg plus 2.3 for women. Robinson uses 52 kg plus 1.9 for men and 49 kg plus 1.7 for women. Miller uses 56.2 kg plus 1.41 for men and 53.1 kg plus 1.36 for women. Hamwi uses 48 kg plus 2.7 for men and 45.5 kg plus 2.2 for women.
Formulas vs the healthy BMI range
The formulas give a single figure, while the BMI range gives a span. For a height of 180 cm the BMI range runs from about 59.9 kg to 80.7 kg, much wider than the four formula results. If you are inside the range, your weight is not a concern by this measure. The BMI Calculator shows your own BMI.
Why one number is misleading
A single ideal number can look more exact than it is, which is why this page shows four and a range.
- Frame size and bone density vary between people
- Muscle weighs more than fat
- Age and ethnicity change what is healthy
- The formulas were built for average adults, not athletes
Using the result sensibly
Treat the numbers as a starting point for a conversation with a doctor or dietitian, not a target to hit. If you want to change your weight, the Calorie Calculator estimates daily energy needs, and the Sleep Calculator helps plan rest. To compare two weights as a percentage change, use the Percentage Calculator. This is not medical advice.
Features
- Devine, Robinson, Miller and Hamwi formulas
- Average of the four formulas
- Healthy weight range for BMI 18.5 to 24.9
- Height in cm or feet and inches
- Results in kg and lb
- Runs in your browser
Frequently asked questions
What is my ideal weight for my height?
There is no single answer. For a man of 180 cm the four formulas give between about 71.5 and 77.3 kg, and for a woman of 165 cm between about 56.4 and 59.9 kg. Enter your height to see your own range.
Which ideal weight formula is best?
None is best. Each was built from limited data at a different time: Hamwi in 1964, Devine in 1974, and Robinson and Miller in 1983. They tend to differ by a few kilograms, so it makes sense to look at the range or the average.
What is a healthy BMI range?
A BMI of 18.5 to 24.9 is usually treated as the healthy range for adults. The page turns that into weights for your height by multiplying the BMI limits by your height in metres squared.
Does the formula work for short or tall people?
The formulas add a set amount per inch above 5 feet. Below 5 feet this page treats the extra term as 0, so it shows the base weight. For very short or very tall people the healthy BMI range is a better guide.
Is ideal weight the same for men and women?
No. Each formula has a different base and increase per inch for men and women, so at the same height the result is a few kilograms higher for men.
Does muscle change my ideal weight?
Yes. Muscle is denser than fat, so a muscular person can weigh more than these formulas suggest and still be lean. Body fat is often a better guide than weight alone, and the Body Fat Calculator estimates it.
Do the formulas use age?
No. All four use only height and sex, so the calculator does not ask for age.