Ideal Weight Calculator
Free ideal weight calculator: your healthy weight range by the Devine, Robinson, Miller and Hamwi formulas plus the WHO BMI band, from your height.
updated
- ✓ Runs in your browser — nothing uploaded
- ✓ No sign-up
- ✓ Free, no limits
| Devine (1974) — used in medicine | 75.0 kg |
| Robinson (1983) | 72.6 kg |
| Miller (1983) | 71.5 kg |
| Hamwi (1964) | 77.3 kg |
The formulas ignore muscle, frame and age — treat the band as orientation, not a target. Not medical advice.
This calculator answers "what should I weigh for my height?" the honest way: with all four published ideal-body-weight formulas side by side — Devine (1974, the one behind most medical dosing), Robinson (1983), Miller (1983) and Hamwi (1964) — plus the WHO healthy-BMI range, which modern guidance prefers because it gives a band rather than a single number.
Each formula starts from a base weight at five feet and adds a fixed amount per inch of height above it, with separate coefficients for men and women. Worked example: a 180 cm man is 75.0 kg by Devine, 72.6 by Robinson, 71.5 by Miller and 77.3 by Hamwi — while the WHO band for that height runs from about 60 to 80 kg.
The spread between formulas is the real lesson: 'ideal' weight is a range, not a point, and none of these account for muscle mass, frame or age. Use the band for orientation, the BMI and body-fat tools for context, and a clinician for decisions. Nothing you enter leaves your browser.
Frequently asked questions
What is my ideal weight for my height?
There is no single number — the four standard formulas disagree by several kilograms by design. The calculator shows all four plus the WHO healthy-BMI range for your height, which is the more modern way to think about it.
Why do doctors use the Devine formula?
It was built for drug dosing, and medicine kept it: many medication doses are still calculated from Devine ideal body weight. That history is why it remains the most cited of the four.
Do these formulas work for very short or very muscular people?
Poorly. Below five feet the formulas extrapolate badly, and none of them see muscle: a lean, muscular person can sit far above every formula while being perfectly healthy. Treat the outputs as reference points.