Ideal Weight Calculator (Devine, Robinson, Miller, Hamwi)
Find your ideal weight with the Devine, Robinson, Miller, and Hamwi formulas from height and sex, plus the healthy BMI weight band and current-weight comparison.
Ideal Weight — interactive calculator, computed instantly in your browser.
Ideal Weight Formulas: Devine, Robinson, Miller and Hamwi Compared
Four Estimates for a 180 cm Male (kg)
Ideal body weight formulas estimate a healthy target from height and sex alone. The four classics — Devine, Robinson, Miller, and Hamwi — all share one structure: a base weight for people at 5 feet tall, plus a per-inch allowance above that mark. None is a verdict on health; they are starting points that the BMI band and body composition refine.
1. The Four Formulas, Side by Side
- Devine (1974): built for drug dosing — male base 50 kg, female 45.5 kg, +2.3 kg per inch over 5 ft
- Robinson (1983): 52 / 49 kg bases with +1.9 (male) and +1.7 (female) per inch — slightly conservative
- Miller (1983): 56.2 / 53.1 kg bases with +1.41 / +1.36 per inch — highest bases, flattest slope
- Hamwi (1964): 48 / 45.4 kg bases with +2.7 / +2.2 per inch — steepest climb, often the highest result for tall people
- Under 5 ft the deduction is skipped — the base value itself is the estimate
2. The Healthy BMI Band Around Them
For 180 cm: 18.5 × 3.24 = 59.9 kg and 24.9 × 3.24 = 80.7 kg — the four formulas (71.5–77.3 kg) all land inside it, which is the point: they are anchors within a band, not a single number on the scale. Health organizations serving Asian populations often tighten the upper cutoff to 23 because cardiometabolic risk rises earlier.
3. How to Use These Numbers Well
- Treat the spread across the four formulas as your tolerance — a 5 kg window is normal, chasing one exact figure is not
- Frame and muscle mass break the model: a muscular 180 cm adult can sit above Hamwi's number at a lean body-fat percentage
- Pair with body fat percentage (Navy tape method) and waist-to-height ratio for a composition-aware picture
- Targets should trend, not snap — a sustainable 0.5 kg per week beats any formula's exact figure
🔗 Body Metrics Cross-References
Ideal weight formulas give a target; body composition tells you what that weight is made of — explore our 💚 Health Hub for BMI, body fat, and macro tools.
Pair a target weight with calorie and macro splits to plan how to get there.
Frequently Asked Questions (Ideal Weight)
None is clinically definitive — they correlate with insurance-table data rather than measured outcomes. Devine anchors drug dosing, Miller tends to fit taller adults, Hamwi runs higher for tall frames. The smartest approach is to average all four and treat their spread as your healthy tolerance window.
Multiply your height in metres squared by 18.5 and by 24.9 to bracket the normal BMI band. At 170 cm that is 53.5 to 72.0 kg; at 160 cm it is 47.4 to 63.7 kg — then check where the four formula estimates fall inside that band for a second opinion.
They were derived from actuarial tables where 60 inches was the reference height, so each carries a base weight at exactly 5 ft plus a per-inch adjustment above it. For people shorter than 5 ft the per-inch term would go negative, so practice stops at the base value.
No — every formula uses a lower base and generally a smaller per-inch allowance for women, reflecting typical differences in height, skeletal frame, and essential body-fat percentage. Comparing a man's and a woman's ideal weight at the same height is not meaningful.