Ideal Weight Formulas Compared: Devine, Robinson, Miller & Hamwi
September 18, 2026
There's no single scientifically 'correct' ideal weight formula — Devine, Robinson, Miller, and Hamwi were each developed independently, mostly for medical dosing purposes, and they produce slightly different results for the same height because they were built from different reference populations.
Skip the math and get your answer instantly:
Open the Ideal Weight Calculator →Where Each Formula Came From
| Formula | Origin | Base Weight (Men, 5'0") |
|---|---|---|
| Devine (1974) | Originally created for medical drug dosing calculations | 50.0 kg |
| Robinson (1983) | A refinement of Devine using updated data | 52.0 kg |
| Miller (1983) | Another Devine refinement, slightly different constants | 56.2 kg |
| Hamwi (1964) | Originally developed for diabetic diet planning | 48.0 kg |
Why They Don't Fully Agree
Each formula adds a fixed per-inch increment (typically 2.3-2.7 kg per inch over 5 feet) to a different base weight, and those base weights and increments were derived from different studies and different original purposes — none were designed as a universal 'ideal weight' standard, which is why modern clinicians treat all of them as rough reference ranges rather than precise targets.
What to Actually Do With These Numbers
Because these formulas only use height (not frame size, muscle mass, or body composition), the more useful approach is to look at the range across all four formulas as a rough reference point, then weigh it against other markers like BMI, body fat percentage, and how you actually feel and perform — not treat any single formula's output as a precise personal target.
Frequently Asked Questions
Which ideal weight formula is most accurate?
None is definitively 'most accurate' — they were developed for different original purposes (mostly medical dosing) using different reference data, so they're best used together as a rough range rather than trusting any single one as precise.
Why was the Devine formula originally created?
It was developed in 1974 specifically to help calculate accurate medication dosing, not as a general wellness or fitness target — its widespread use for 'ideal weight' came later.
Do these formulas account for muscle mass or body frame?
No — all four formulas use only height (and sex), so they don't account for muscle mass, bone structure, or frame size, which is a significant limitation for athletic or larger-framed individuals.
Why do the formulas give different results for the same height?
Each was calibrated against a different original data set and study population, resulting in different base weights and per-inch increments even though the general structure (a base weight plus an increment per inch of height) is similar across all four.
Should I aim for the exact number one formula gives me?
Not necessarily — treat the spread across formulas as a rough healthy range rather than a precise target, and weigh it alongside other measures like body composition, fitness level, and how you feel.