Ideal Weight Calculator
Compare your ideal body weight from the Devine, Robinson, Miller and Hamwi formulas with the healthy BMI weight range for your height.
Verified October 2026 · Sources: Pai & Paloucek, Ann Pharmacother 2000; WHO BMI; NICE NG246
Devine: 50 kg + 2.3 kg × 8.90 = 70.5 kg
Robinson: 52 kg + 1.9 kg × 8.90 = 68.9 kg
Miller: 56.2 kg + 1.41 kg × 8.90 = 68.7 kg
Hamwi: 48 kg + 2.7 kg × 8.90 = 72.0 kg
Healthy BMI range = 18.5 × 1.75² to 24.9 × 1.75²
Ideal weight at nearby heights
| Height | Formula range | Average | Healthy BMI range |
|---|---|---|---|
| 165.0 cm | 61 kg – 63 kg | 61.9 kg | 50 kg – 68 kg |
| 170.0 cm | 65 kg – 67 kg | 65.9 kg | 53 kg – 72 kg |
| 175.0 cm | 69 kg – 72 kg | 70.0 kg | 57 kg – 76 kg |
| 180.0 cm | 72 kg – 77 kg | 74.1 kg | 60 kg – 81 kg |
| 185.0 cm | 74 kg – 83 kg | 78.2 kg | 63 kg – 85 kg |
- Treating one formula's number as a strict target — use the range across formulas and BMI.
- Measuring height in shoes or slouching — stand straight against a wall, barefoot.
- Ignoring muscle: athletes are often healthy above their formula weight.
- Using adult formulas for teenagers or during pregnancy — they don't apply.
- Aiming for the bottom of the range by default — anywhere in the healthy range can be fine.
- →Check your BMI category and waist-to-height ratio with the BMI Calculator.
- →If you want to change weight, the Calorie Calculator gives a daily target at a safe pace.
- →Estimate your body fat percentage — it says more about health than weight alone.
- →Discuss any weight goal with a doctor or registered dietitian if you have a health condition.
This tool is for informational purposes only. Always verify results with a qualified professional.
What is the Ideal Weight Calculator?
An ideal weight calculator estimates a sensible body weight for your height and sex. There is no single 'perfect' weight, so this tool shows the four best-known ideal body weight (IBW) formulas — Devine, Robinson, Miller and Hamwi — side by side, together with the healthy weight range from BMI. Seeing them together gives a realistic target range instead of one number to chase.
All four formulas work the same way: a base weight at 5 feet (152.4 cm) plus a fixed amount for every inch above that. Devine (1974): men 50 kg + 2.3 kg per inch, women 45.5 kg + 2.3 kg per inch. Robinson (1983): men 52 kg + 1.9 kg, women 49 kg + 1.7 kg. Miller (1983): men 56.2 kg + 1.41 kg, women 53.1 kg + 1.36 kg. Hamwi (1964): men 48 kg + 2.7 kg, women 45.5 kg + 2.2 kg. A review in the Annals of Pharmacotherapy (Pai and Paloucek, 2000) traced their origins: the Devine formula was introduced for drug dosing, and the formulas agree closely because they were all fitted to similar insurance height-weight tables. They are still widely used in hospitals to dose some medicines.
Worked example: for a man 175 cm (5 ft 8.9 in) tall, height is 8.9 inches above 5 ft. Devine gives 50 + 2.3 × 8.9 = 70.5 kg, Robinson 68.9 kg, Miller 68.7 kg and Hamwi 72.0 kg — an average of 70.0 kg (154 lb). The healthy BMI range of 18.5–24.9 at the same height is 56.7–76.3 kg, so the formulas sit comfortably inside the BMI range, near its upper middle.
The BMI-based healthy range is the one most health services use. It is calculated as 18.5 × height² to 24.9 × height² (height in metres), using WHO cut-offs. If you are of South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean background, the UK's NICE guideline uses a lower upper limit of BMI 23, so this calculator offers an Asian cut-off option that caps the range at BMI 22.9.
Ideal weight formulas have clear limits: they ignore muscle mass, frame size, age and body composition, and they were designed for adults over 5 ft — for shorter heights the numbers are extrapolated and can be unrealistically low. They also do not apply to children, teenagers or pregnant women. Use the range as a guide for conversation with a doctor or dietitian, not as a strict target.
How to Use This Calculator
- 1Choose metric or imperial units and select your sex — the formulas differ for men and women.
- 2Enter your height in cm, or feet and inches.
- 3Optionally enter your current weight to see how it compares with each estimate.
- 4Choose WHO or Asian BMI cut-offs for the healthy BMI range.
- 5Compare the four formula results, their average and the BMI range in the chart and table.
- 6Use the height table to see how the numbers change a few cm or inches either way.