Estimate a reference body weight range for your height using three commonly cited formulas, alongside the healthy weight range from BMI.
| Robinson formula | – |
| Hamwi formula | – |
| Healthy BMI range (18.5–24.9) | – |
How it works
These are older reference formulas originally created for medication dosing, not fitness targets. Devine: 50 kg (men) or 45.5 kg (women) + 2.3 kg for each inch over 5 feet. Robinson and Hamwi use similar patterns with different starting numbers. None of them account for muscle mass, bone structure or frame size, which is why the BMI-based healthy range is shown alongside them for comparison.
Example
A 5 ft 9 in (175 cm) man is 9 inches over 5 feet. Devine formula: 50 + 2.3 × 9 = 70.7 kg (about 155.9 lb).
Frequently asked questions
Which formula is most accurate?
None is definitively "correct" for everyone. They were designed for drug dosing and are commonly cited as rough reference points, not fitness or medical targets.
Why do the formulas give different answers?
Each was developed from a different population and study, so they use slightly different assumptions.
More free tools: BMI calculator · Calorie calculator · All free tools
This calculator gives general estimates for information only and is not medical advice. Formulas are population averages and do not account for frame size or muscle mass. Talk to a doctor for personal guidance.