Ideal Weight Calculator
Find your ideal body weight for your height using the Devine, Robinson and Miller formulas, plus the healthy weight range from BMI. For adult men and women.
🎯 Ideal Weight Calculator
Ideal Weight (kg)
💡 How the Ideal Weight Calculator Works
This calculator estimates an ideal body weight (IBW) for your height and sex with three established formulas, and shows the weight range that gives a healthy BMI. For a man 170 cm tall, the formulas give 65.9 kg (Devine), 65.2 kg (Robinson) and 66.0 kg (Miller), and a healthy BMI corresponds to 53.5–72.0 kg.
The formulas give a single reference number; the BMI range is the better guide to a healthy weight for most adults, since healthy bodies differ in build and muscle.
The ideal body weight formulas
Each formula starts with a base weight at 5 feet (152.4 cm) and adds a fixed amount for every inch above that.
| Formula | Men | Women |
|---|---|---|
| Devine (1974) | 50 kg + 2.3 kg per inch over 5 ft | 45.5 kg + 2.3 kg per inch over 5 ft |
| Robinson (1983) | 52 kg + 1.9 kg per inch over 5 ft | 49 kg + 1.7 kg per inch over 5 ft |
| Miller (1983) | 56.2 kg + 1.41 kg per inch over 5 ft | 53.1 kg + 1.36 kg per inch over 5 ft |
Lower limit = 18.5 × height² · Upper limit = 24.9 × height²
Worked example: man, 170 cm
- Inches over 5 ft: 170 ÷ 2.54 = 66.93 in, minus 60 = 6.93 in.
- Devine: 50 + 2.3 × 6.93 = 65.9 kg.
- Robinson: 52 + 1.9 × 6.93 = 65.2 kg.
- Miller: 56.2 + 1.41 × 6.93 = 66.0 kg.
- BMI range: 18.5 × 1.7² = 53.5 kg to 24.9 × 1.7² = 72.0 kg.
For a woman 160 cm tall: Devine 52.4 kg, Robinson 54.1 kg, Miller 57.2 kg, BMI range 47.4–63.7 kg.
Ideal weight chart for men
Values in kg.
| Height | Devine | Robinson | Miller | Healthy BMI range |
|---|---|---|---|---|
| 160 cm | 56.9 | 57.7 | 60.4 | 47.4–63.7 |
| 165 cm | 61.4 | 61.4 | 63.2 | 50.4–67.8 |
| 170 cm | 65.9 | 65.2 | 66.0 | 53.5–72.0 |
| 175 cm | 70.5 | 68.9 | 68.7 | 56.7–76.3 |
| 180 cm | 75.0 | 72.6 | 71.5 | 59.9–80.7 |
| 185 cm | 79.5 | 76.4 | 74.3 | 63.3–85.2 |
| 190 cm | 84.0 | 80.1 | 77.1 | 66.8–89.9 |
Ideal weight chart for women
Values in kg.
| Height | Devine | Robinson | Miller | Healthy BMI range |
|---|---|---|---|---|
| 155 cm | 47.9 | 50.7 | 54.5 | 44.4–59.8 |
| 160 cm | 52.4 | 54.1 | 57.2 | 47.4–63.7 |
| 165 cm | 56.9 | 57.4 | 59.8 | 50.4–67.8 |
| 170 cm | 61.4 | 60.8 | 62.5 | 53.5–72.0 |
| 175 cm | 66.0 | 64.1 | 65.2 | 56.7–76.3 |
| 180 cm | 70.5 | 67.5 | 67.9 | 59.9–80.7 |
| 185 cm | 75.0 | 70.8 | 70.6 | 63.3–85.2 |
The formulas agree closely around average heights and spread apart for very tall people, because Devine adds the most per inch and Miller the least. At 190 cm, for example, Devine gives about 7 kg more than Miller for men.
Where the formulas come from
None of these equations was designed to tell people what they should weigh. Devine published his equations in 1974 in a paper on dosing the antibiotic gentamicin, where they were used to estimate kidney function for drug doses. A 2000 review in the Annals of Pharmacotherapy by Pai and Paloucek found that Devine gave no data source; they appear to be a metric version of an older rule of thumb (100 lb at 5 ft plus 5 lb per inch for women, 110 lb for men).
Robinson and colleagues (1983) fitted their equations to the 1959 Metropolitan Life Insurance height-weight tables, and Miller and colleagues (1983) to the 1983 tables. Those tables linked weight with lowest mortality among insured people, not with fitness or body composition. The review concluded that the equations are similar because the tables behind them broadly agree, and any of them can be used as an estimate.
How ideal body weight is used in medicine
Devine's formula is still widely used in hospitals: to calculate doses of some medicines, to set breathing volumes on mechanical ventilators, and in nutrition assessment. For people well above their IBW, clinicians often use an adjusted body weight instead. These are clinical tools; your own dose or ventilator settings should always come from your care team.
BMI weight categories
The healthy weight range comes from the standard adult BMI categories used by the CDC and the World Health Organization:
| BMI | Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 to under 25 | Healthy weight |
| 25 to under 30 | Overweight |
| 30 to under 35 | Obesity class 1 |
| 35 to under 40 | Obesity class 2 |
| 40 or more | Obesity class 3 (severe) |
Check your current BMI with the BMI calculator.
Limitations
- Body composition: neither the formulas nor BMI distinguish muscle from fat. A muscular person can sit above both and be very healthy. The body fat calculator and lean body mass calculator give a fuller picture.
- Frame and build: people with broader frames naturally weigh more at the same height.
- Short heights: the formulas were built for people 5 ft (152.4 cm) and taller. Below that, this calculator returns the 5 ft value, so a woman of 145 cm gets 45.5 kg (Devine), the same as at 152.4 cm. Some clinicians subtract the per-inch amount instead; the BMI range (38.9–52.4 kg at 145 cm) is more useful here.
- Age and ethnicity: the formulas don't adjust for age, and BMI cut-offs may not suit everyone; for example, health risks can rise at lower BMIs in some Asian populations.
- Not for children or pregnancy: children and teens need age- and sex-specific charts; see the child and teen BMI calculator.
Using your result
If your weight is within the BMI range, the formulas' exact number matters little. If you want to change weight, a gradual approach works best: the calorie calculator and TDEE calculator estimate your daily energy needs. Waist size also adds useful information about health risk; try the waist-to-height ratio calculator. For personal targets, especially with a medical condition, talk to a doctor or registered dietitian.
Sources
- Pai MP, Paloucek FP (2000). The origin of the "ideal" body weight equations. Annals of Pharmacotherapy, 34(9), 1066–1069
- Devine BJ (1974). Gentamicin therapy. Drug Intelligence and Clinical Pharmacy, 8, 650–655.
- Robinson JD, Lupkiewicz SM, Palenik L, Lopez LM, Ariet M (1983). Determination of ideal body weight for drug dosage calculations. American Journal of Hospital Pharmacy, 40, 1016–1019.
- Miller DR, Carlson JD, Loyd BJ, Day BJ (1983). Determining ideal body weight (letter). American Journal of Hospital Pharmacy, 40, 1622.
- Centers for Disease Control and Prevention: Adult BMI categories