Ideal Weight Calculator: Devine, Robinson, Miller and Hamwi Formulas
Free ideal weight calculator: enter your height and sex to see your ideal body weight by the Devine, Robinson, Miller and Hamwi formulas next to the healthy BMI range, with charts of where the formulas land and ideal weight at every height.
Where the formulas land
Each formula
Ideal weight at every height
The shaded band is the healthy BMI range (18.5–24.9). The dashed line marks your height.
How ideal body weight is calculated
There is no single “ideal” weight, so this calculator shows four classic formulas side by side with the healthy BMI range. Each formula starts from a base weight at 5 feet (152.4 cm) and adds a fixed number of kilograms for every inch above it:
For example, a man of 180 cm (70.9 in, 10.9 inches over 5 ft) has a Devine ideal weight of 50 + 2.3 × 10.9 = 75 kg (165 lb).
Ideal weight versus healthy weight range
The formulas give a single number and ignore build, age and muscle. The healthy BMI range (BMI 18.5 to 24.9) gives a band of weights that is more realistic: anywhere inside it is generally considered healthy for adults. Most people do well somewhere in the middle of the band, and athletes with a lot of muscle can sit above it without any excess fat.
Questions
- Which formula is the most accurate?
- None is “right”. They were written for different purposes (the Devine formula to dose medicine) and disagree by a few kilos. Look at the range, not one number.
- Do the formulas work below 5 feet or for very tall people?
- They are extended in a straight line, so they get less reliable at the extremes. The healthy BMI band is better there.
- Does age matter?
- These formulas ignore age; adults over 60 often do well slightly above the middle of the BMI range. Children and teens need growth charts.
- Is my data private?
- Yes. Everything stays in this browser.
This is general information, not medical advice. Related: BMI Calculator · Body Fat Calculator · BMR Calculator