Enter your height and sex to see your ideal body weight calculated four different ways: Devine, Robinson, Miller, and Hamwi.

How to Use the Ideal Weight Calculator

Select Male or Female, choose Metric or US units, then enter your height — all four formulas below calculate at once, so there's nothing else to toggle.

"Ideal weight" sounds like a wellness term, but none of the four formulas here were built for that purpose. Devine, Robinson, Miller, and Hamwi all came out of clinical pharmacy — a practical need to estimate a standardized body weight for calculating drug doses, particularly for patients whose actual weight might be skewed by fluid retention, amputation, or obesity, where dosing off the number on the scale would be inappropriate.

Four Formulas, One Basic Shape

Devine (1974):   Men 50.0 + 2.3 × in    Women 45.5 + 2.3 × in
Robinson (1983): Men 52.0 + 1.9 × in    Women 49.0 + 1.7 × in
Miller (1983):   Men 56.2 + 1.41 × in   Women 53.1 + 1.36 × in
Hamwi (1964):    Men 48.0 + 2.7 × in    Women 45.5 + 2.2 × in

All results in kilograms, with "in" meaning inches of height over 5 feet. Every formula follows the identical shape — a base weight at exactly 5 feet, plus a fixed increment per inch above that — which makes the disagreement between them easy to see: same structure, different numbers, because each was fit to a different reference population at a different point in time.

Hamwi is the oldest of the four, developed by G.J. Hamwi in 1964 originally for diabetic diet planning. Devine followed in 1974 and became, by a wide margin, the version most clinical pharmacists still reach for when calculating a drug dose today. Robinson and Miller both arrived in 1983, proposed as refinements, and neither ever displaced Devine's dominant clinical use. This calculator shows all four side by side rather than picking a winner — none is more "correct" than the others, just four separate attempts at the same estimate.

Not the Same as a Healthy Weight Target

It's easy to assume "ideal weight" and "healthy weight" are two names for the same calculation. They aren't. The site's Healthy Weight Calculator works backward from the WHO's BMI bands — a population health screening range. These four formulas were never validated against health outcomes at all; they were built to answer a dosing question, not a wellness one. A result here landing outside your actual weight says nothing about your health — it says a decades-old drug-dosing convention and your current weight don't match, a different fact entirely.

Not a personal health target. These formulas were developed for medical dosing calculations, not as fitness or wellness goals. Talk to a doctor or registered dietitian about what a healthy weight looks like for you.