worldofcalcsIdeal Weight Calculator
What is an ideal body weight?
Ideal body weight (IBW) formulas estimate a sensible weight for your height and sex. They were developed by doctors in the 1960s–80s, mainly to work out medicine doses, and are still widely used. They give a single number, so treat them as a guide alongside a healthy BMI range rather than an exact target.
Ideal weight formulas
Robinson: men 52 + 1.9 kg, women 49 + 1.7 kg per inch over 5 feet. Miller: men 56.2 + 1.41 kg, women 53.1 + 1.36 kg. Hamwi: men 48 + 2.7 kg, women 45.5 + 2.2 kg. Five feet is 152.4 cm and an inch is 2.54 cm. The formulas don't account for frame size or muscle, so a range is more useful than any one result.
Using your ideal weight
- The formulas were built on Western populations. For Indians, a weight that keeps BMI between 18.5 and 22.9 is a better guide.
- They don't know how muscular you are, so athletes are often healthily above their 'ideal' weight.
- Below 5 feet the formulas become unreliable; use the BMI range instead.
- Waist size and how you feel matter more than reaching an exact number.
- These are estimates for healthy adults. Speak to a doctor or dietitian if you are pregnant, have a medical condition or plan a big change in diet.
Worked example
- A man 170 cm tall is 6.93 inches over 5 feet ((170 − 152.4) ÷ 2.54)
- Robinson: 52 + 1.9 × 6.93 = 65.2 kg; Devine: 50 + 2.3 × 6.93 = 65.9 kg
- Miller: 66.0 kg; Hamwi: 66.7 kg, so the formulas agree on about 65–67 kg
- A woman 160 cm tall gets 52.1–57.2 kg from the four formulas
Ideal weight by height
Devine formula, with the weight range for a BMI of 18.5–22.9 (Indian guideline).
| Height | Men (Devine) | Women (Devine) | Healthy range (BMI 18.5–22.9) |
|---|---|---|---|
| 152 cm | 49.6 kg | 45.1 kg | 42.7–52.9 kg |
| 155 cm | 52.4 kg | 47.9 kg | 44.4–55.0 kg |
| 160 cm | 56.9 kg | 52.4 kg | 47.4–58.6 kg |
| 165 cm | 61.4 kg | 56.9 kg | 50.4–62.3 kg |
| 170 cm | 65.9 kg | 61.4 kg | 53.5–66.2 kg |
| 175 cm | 70.5 kg | 66.0 kg | 56.7–70.1 kg |
| 180 cm | 75.0 kg | 70.5 kg | 59.9–74.2 kg |
| 185 cm | 79.5 kg | 75.0 kg | 63.3–78.4 kg |
Rounded to 0.1 kg.
Frequently Asked Questions
Ideal Weight Range Table
Comparison of ideal body weight formulas by height. The highlighted row shows the average height for your selected country and gender.
| Height | Robinson | Devine | Miller | Hamwi | Average |
|---|---|---|---|---|---|
| 4'10" (147 cm) | 48 kg | 45 kg | 53 kg | 43 kg | 47 kg |
| 4'11" (150 cm) | 50 kg | 48 kg | 55 kg | 45 kg | 49 kg |
| 5'0" (152 cm) | 52 kg | 50 kg | 56 kg | 48 kg | 52 kg |
| 5'1" (155 cm) | 54 kg | 52 kg | 58 kg | 51 kg | 54 kg |
| 5'2" (157 cm) | 56 kg | 55 kg | 59 kg | 53 kg | 56 kg |
| 5'3" (160 cm) | 58 kg | 57 kg | 60 kg | 56 kg | 58 kg |
| 5'4" (163 cm) | 60 kg | 59 kg | 62 kg | 59 kg | 60 kg |
| 5'5" (165 cm) | 61 kg | 61 kg | 63 kg | 61 kg | 62 kg |
| 5'6" (168 cm) | 63 kg | 64 kg | 65 kg | 64 kg | 64 kg |
| 5'7" (170 cm) | 65 kg | 66 kg | 66 kg | 67 kg | 66 kg |
| 5'8" (173 cm) | 67 kg | 68 kg | 67 kg | 70 kg | 68 kg |
| 5'9" (175 cm) | 69 kg | 71 kg | 69 kg | 72 kg | 70 kg |
| 5'10" (178 cm) | 71 kg | 73 kg | 70 kg | 75 kg | 72 kg |
| 5'11" (180 cm) | 73 kg | 75 kg | 72 kg | 78 kg | 74 kg |
| 6'0" (183 cm) | 75 kg | 78 kg | 73 kg | 80 kg | 76 kg |
| 6'1" (185 cm) | 77 kg | 80 kg | 75 kg | 83 kg | 79 kg |
| 6'2" (188 cm) | 79 kg | 82 kg | 76 kg | 86 kg | 81 kg |
| 6'3" (191 cm) | 81 kg | 85 kg | 77 kg | 89 kg | 83 kg |
| 6'4" (193 cm) | 82 kg | 87 kg | 79 kg | 91 kg | 85 kg |
| 6'5" (196 cm) | 84 kg | 89 kg | 80 kg | 94 kg | 87 kg |
| 6'6" (198 cm) | 86 kg | 91 kg | 82 kg | 97 kg | 89 kg |
About the Formulas
- Robinson (1983): Most commonly used formula, moderately conservative estimates.
- Devine (1974): Originally developed for drug dosage calculations, tends to give higher values for taller people.
- Miller (1983): Produces slightly higher baseline weights, flatter increase per inch.
- Hamwi (1964): One of the earliest formulas, commonly used in clinical settings.