Enter your height and sex to see what four published formulas suggest, and how far apart they land.
Estimates are for general guidance only and are not medical advice. For a personalised plan, book a free guided tour at RPM Gym.
You get five numbers: four formula results and their average. The spread between them is the useful part. For most adults the four land within four or five kilograms of each other, which tells you something the headline average hides — none of them is measuring you.
All four are height-based. They take no account of your frame, your muscle, your training history or where you carry weight, because they were never built to. Devine wrote his in 1974 to scale drug doses to body size. The others adjusted his intercepts against different populations. None was designed to tell a gym member what to weigh.
h = height in inches above 60 Devine men 50.0 + 2.3h · women 45.5 + 2.3h Robinson men 52.0 + 1.9h · women 49.0 + 1.7h Miller men 56.2 + 1.41h · women 53.1 + 1.36h Hamwi men 48.0 + 2.7h · women 45.5 + 2.2h
A man of 178 cm.
Four published formulas, a 4.8 kg spread, and an average of 72.5 kg. Treating 72.5 as a target while ignoring that Hamwi says 75.2 and Miller says 70.4 is reading precision into a disagreement.
None of them is accurate about an individual, because none measures anything about you except height. Robinson and Miller were both attempts to improve on Devine and both landed somewhere different, which is the clearest evidence available that there is no single right answer here.
They were fitted to different reference populations and use different intercepts and slopes. Hamwi came first, in 1964, from clinical practice. Devine followed in 1974 for drug dosing. Robinson and Miller both published revisions in 1983 using different data. Each is internally consistent and none agrees with the others.
No. A healthy BMI is a band derived from population health data, and it covers a wide weight range at any height. These formulas produce a single point from a linear equation. They answer different questions and the point often sits below the middle of the BMI band.
As a rough orientation, yes. As a target to chase, no. A goal weight is more useful when it comes from where you are now, how fast you can sensibly change, and what you want your training to do — not from a formula that only knows how tall you are.
It can't. Height is the only body measurement it takes. That's why a lifter almost always reads above every one of these numbers while carrying less fat than someone reading below them.
Bring the numbers to a free guided tour at RPM Gym in Al Manhal and we'll look at composition and training, which is where the useful version of this question lives.