Search for your “ideal weight” and you will meet a handful of formulas with different answers. Devine, Robinson, Miller, and Hamwi all take your height and sex and spit out a target — but they were built for different purposes, so treat their output as a range, not a verdict.
Where these formulas came from
Most were originally created to calculate medication dosages, not to define beauty or fitness. The Devine formula (1974) is the best known and underpins many clinical calculations. Robinson and Miller refined it with slightly different coefficients, while Hamwi offers a fast mental estimate.
Why they disagree
For a 5-foot-10 man, the formulas can land anywhere from about 70 to 76 kg. None of them account for frame size, muscle mass, or age, which is why an athlete can be “overweight” by these numbers while being extremely healthy. The spread between formulas is roughly your margin of error.
A better approach
Use the formulas to find a sensible range, then cross-check with body fat percentage and how you feel and perform. A muscular person should trust body composition over any height-weight formula.
Frequently asked questions
Which formula is most accurate?
None is definitively best. Devine is the clinical standard, but a range across formulas is more honest than any single figure.
Do these work for very tall or short people?
They lose accuracy at the extremes, since they were fitted to average heights.
Try it yourself
Skip the manual math — use a free tool and get the answer instantly:
Results are general information only and not professional financial, medical, or legal advice.