Ideal Weight Calculator
Enter your height and sex to see ideal body weight from the two classic clinical formulas — plus the healthy BMI range for context.
How the math works
Hamwi (1964): men 48 kg + 2.7 kg/in · women 45.5 kg + 2.2 kg/in
"Ideal body weight" comes from clinical formulas originally built to dose medications correctly, not to set fitness goals. Devine became the standard for drug dosing; Hamwi came from dietetics. They disagree by a few kilograms, especially above 6 feet — which is normal and exactly why we also show your healthy BMI range (18.5–24.9), a band rather than a single number, and usually the more honest target.
How to use these numbers
Treat IBW as a reference point, not a verdict. Body composition (muscle vs fat), frame size, and where you carry weight all matter more than any formula. If your current weight sits inside the healthy BMI band and you train, sleep and eat well, the formulas have nothing to add. If you're far outside the band, the direction they point is still useful.
FAQ
- Which formula should I trust?
- None exclusively. Devine is the most cited; the BMI range is the broadest-supported by outcomes data. Use them as a range, not a rule.
- Do the formulas account for age or muscle?
- No. A muscular athlete can be "overweight" by IBW while perfectly lean, and healthy weight naturally shifts somewhat across decades of life.
- What's a healthy body fat percentage instead?
- Roughly 10–20% for men and 18–28% for women by the Navy tape method — see our body fat calculator.
This tool provides general information only and is not medical advice. Talk to a qualified healthcare professional about your personal weight goals.