Ideal Weight Calculator
There is no single “ideal weight” — there are four clinical formulas, each built for a different purpose, and they rarely agree. See them all at once, plus the healthy BMI range most doctors actually use.
How to use this calculator
- Choose units and your sex (the formulas differ by sex).
- Enter your height — that is the only measurement these formulas use.
- Compare all four estimates against the healthy BMI range, and remember lean people run heavy on a scale.
The four formulas
Each formula starts from a base weight at 5 ft (152 cm) and adds a fixed amount per inch above it:
| Formula | Men (base + per inch) | Women (base + per inch) | Origin |
|---|---|---|---|
| Devine (1974) | 50.0 kg + 2.30 kg | 45.5 kg + 2.30 kg | Drug dosing |
| Robinson (1983) | 52.0 kg + 1.90 kg | 49.0 kg + 1.70 kg | Revision of Devine |
| Miller (1983) | 56.2 kg + 1.41 kg | 53.1 kg + 1.36 kg | Revision of Devine |
| Hamwi (1964) | 48.0 kg + 2.70 kg | 45.5 kg + 2.20 kg | Clinical nutrition |
Note what they ignore: muscle mass, bone structure and body composition. A weightlifting 180 cm man at 15% body fat will blow past every formula and still be perfectly healthy. Treat the numbers as rough anchors, and prefer body-fat percentage or waist-to-height ratio as your real compass.
Frequently asked questions
Why do the four formulas give different answers?
They were derived from different populations and for different jobs — Devine for medication dosing, Hamwi for clinical nutrition. A 3–6 kg spread across them is normal.
Which number should I actually aim for?
The healthy BMI range is the most defensible anchor for the general population. If you train seriously, aim by body-fat percentage instead and let the scale float.
What if I am shorter than 5 ft?
The formulas still compute (they simply subtract from the base weight), but accuracy drifts at the extremes of height. The BMI range remains valid.
Should I adjust for my frame size?
A quick heuristic: wrap your thumb and middle finger around your opposite wrist — overlapping fingers suggest a smaller frame, non-touching a larger one. Then apply the ±10% convention if it helps.