Ideal Weight Calculator
Find your ideal body weight for your height
Free Ideal Weight Calculator
Four trusted formulas plus your healthy weight range
"How much should I weigh for my height?" has no single correct answer — the scientific literature contains at least four respected formulas, each giving a slightly different result. This tool calculates all four at once: Devine (the standard in drug-dosage calculations), Robinson, Miller and Hamwi. Enter your height and gender to see all four results together with your healthy weight range — the weights corresponding to the WHO's BMI band of 18.5-24.9. A few kilograms of spread between formulas is normal: all are estimates derived from average body composition. For muscular athletes or older adults the numbers shouldn't be read in isolation; treat ideal weight as a compass for the healthy range, not a finish line.
Features
Four Formulas
Devine, Robinson, Miller and Hamwi estimates in one place.
Healthy Range
See the BMI-based healthy weight range for your height.
Gender-Specific
Separate calculations for men and women.
Private & Free
No sign-up and nothing leaves your device.
Ideal Weight Formulas
Men (kg; per inch over 60 in = 152 cm)
- Devine: 50 + 2.3 × in
- Robinson: 52 + 1.9 × in
- Miller: 56.2 + 1.41 × in
- Hamwi: 48 + 2.7 × in
Women (kg; same height base)
- Devine: 45.5 + 2.3 × in
- Robinson: 49 + 1.7 × in
- Miller: 53.1 + 1.36 × in
- Hamwi: 45.5 + 2.2 × in
Frequently Asked Questions
Why do ideal weight formulas give different results?
Each formula was derived in a different year on a different population: Hamwi in 1964, Devine in 1974, Robinson and Miller in 1983. A spread of 2-5 kg between them is normal; averaging the four or using the healthy BMI range is the sounder approach.
Which formula is the most accurate?
There is no single 'most accurate' one. The Devine formula is the medical standard for drug dosing; Robinson and Miller are later refinements based on newer data. For everyday use, the healthy BMI range (18.5-24.9) is the most practical reference.
How is the healthy weight range calculated?
Your height squared (in meters) is multiplied by 18.5 and 24.9 — the weight equivalents of the WHO's normal BMI band. Example: for 1.75 m, that's 56.7-76.3 kg.
I'm muscular — do these results apply to me?
Only partially. Neither the formulas nor BMI distinguish muscle from fat, so a weight that looks 'above ideal' can be perfectly healthy in muscular people. Use our body fat and FFMI calculators to see your actual composition.
Does age affect ideal weight?
The formulas don't include age, but research suggests a slightly higher BMI (25-27) can be protective in older adults. Over 65, aim for the range your physician recommends rather than pushing toward the lower bound.
How do I reach my ideal weight?
Knowing the gap is step one; the rest is calorie balance. Plan your daily calorie needs and macro split with our calorie and macro calculators. Consult a health professional before major changes — this tool is not medical advice.