Ideal body weight (IBW) for your height and sex by the Devine, Robinson, Miller and Hamwi formulas, with the healthy BMI weight range.
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For your height the four formulas give 68.7–72 kg (Devine: 70.5 kg), and a healthy BMI corresponds to 56.7–76.6 kg.
Metric restatement of Hamwi's 106 lb at 5 ft plus 6 lb per inch above it. The original pound form gives 0.27 kg more at this height.
Ideal body weight (IBW) formulas start from a base weight at 5 ft (152.4 cm) and add a fixed amount for each inch above it. Devine (1974) uses 50 kg for men and 45.5 kg for women plus 2.3 kg per inch; Robinson, Miller and Hamwi use other bases and slopes. Beside them is the healthy weight range, the span that keeps BMI between the WHO cut-offs of 18.5 and 25.
Clinicians use IBW to dose some drugs and to set ventilator tidal volume, and many people use it as a reference weight. For a man 175 cm tall the four formulas give 68.7 to 72.0 kg, with Devine at 70.5 kg, while the healthy BMI range runs from 56.7 to 76.6 kg.
The equations come from old height-weight tables and ignore frame size, muscle and age. Below 5 ft they are extrapolated. Each gives a single number, whereas the BMI range shows how wide the healthy span is.
Ideal body weight formulas give one reference weight for a height and sex, while a healthy BMI gives a range. At 175 cm, the Devine formula gives 70.5 kg for a man and 66.0 kg for a woman, and a BMI of 18.5 to 25 spans 56.7 to 76.6 kg for both.
Kilograms, rounded to one decimal. At 152.4 cm, exactly 5 ft, each formula returns its base weight:
| Formula sex | Height, cm | Devine | Robinson | Miller | Hamwi | BMI 18.5 boundary | BMI 25 boundary |
|---|---|---|---|---|---|---|---|
| Male | 152.4 | 50.0 | 52.0 | 56.2 | 48.0 | 43.0 | 58.1 |
| Male | 175 | 70.5 | 68.9 | 68.7 | 72.0 | 56.7 | 76.6 |
| Male | 200 | 93.1 | 87.6 | 82.6 | 98.6 | 74.0 | 100.0 |
| Female | 152.4 | 45.5 | 49.0 | 53.1 | 45.5 | 43.0 | 58.1 |
| Female | 175 | 66.0 | 64.1 | 65.2 | 65.1 | 56.7 | 76.6 |
| Female | 200 | 88.6 | 80.9 | 78.6 | 86.7 | 74.0 | 100.0 |
The BMI columns are the same for men and women because BMI uses only height and weight: 18.5 × height² and 25 × height², with height in meters. At 1.75 m, 18.5 × 3.0625 = 56.7 kg and 25 × 3.0625 = 76.6 kg.
A BMI of 25 is where overweight begins, so the healthy range stops just short of the last column.
For drug dosing or other treatment, follow the protocol's formula and a clinician's judgment, not whichever result looks best.
Count the inches you stand above 5 feet, multiply by 2.3 kg, and add 50 kg for a man or 45.5 kg for a woman. That is the Devine formula (1974), built for adults 5 ft and taller. A woman 5 ft 6 in tall is 6 inches over, so her ideal body weight is 45.5 + 2.3 × 6 = 59.3 kg.
The other three formulas use the same steps with different numbers. For the same woman:
From centimeters, subtract 152.4 and divide by 2.54 to get the inches over 5 ft. A man 170 cm tall is (170 − 152.4) ÷ 2.54 = 6.929 in over, so Devine gives 50 + 2.3 × 6.929 = 65.9 kg.
To convert a result to pounds, divide the kilograms by 0.45359237. Devine's 59.3 kg is 130.7 lb.
The four differ only in their base weight at 5 ft and their slope per inch:
| Formula | Men | Women | Where it came from |
|---|---|---|---|
| Hamwi (1964) | 48 kg + 2.7 kg per inch | 45.5 kg + 2.2 kg per inch | A chapter on diet therapy in an American Diabetes Association book, stated in pounds |
| Devine (1974) | 50 kg + 2.3 kg per inch | 45.5 kg + 2.3 kg per inch | A clinical pharmacy case study on dosing gentamicin |
| Robinson (1983) | 52 kg + 1.9 kg per inch | 49 kg + 1.7 kg per inch | Regression on Metropolitan Life Insurance height and weight tables |
| Miller (1983) | 56.2 kg + 1.41 kg per inch | 53.1 kg + 1.36 kg per inch | A letter in the October 1983 issue of the journal that had published Robinson's paper in June |
Hamwi's original form is 106 lb plus 6 lb per inch for men and 100 lb plus 5 lb per inch for women, as restated in a 2025 Nutrients paper on nutrition after spinal cord injury.
Devine's version appeared in a 1974 case study by McCarron and Devine in Drug Intelligence and Clinical Pharmacy.
Pai and Paloucek (2000) traced all four back to height and weight tables. Weight in those tables was found to track mortality, which is how the words "desirable" and "ideal" attached to it.
Devine's equations matched an older rule of thumb drawn from the tables. Once the handling of some drugs in the body was found to track IBW, Devine's version came into general use for dosing.
Computed from the four formulas, in kilograms. The "all four" column shows the lowest and highest of the four results.
| Height | Men: Devine | Men: all four | Women: Devine | Women: all four |
|---|---|---|---|---|
| 5 ft 0 in (152 cm) | 50.0 | 48.0 to 56.2 | 45.5 | 45.5 to 53.1 |
| 5 ft 2 in (157 cm) | 54.6 | 53.4 to 59.0 | 50.1 | 49.9 to 55.8 |
| 5 ft 4 in (163 cm) | 59.2 | 58.8 to 61.8 | 54.7 | 54.3 to 58.5 |
| 5 ft 6 in (168 cm) | 63.8 | 63.4 to 64.7 | 59.3 | 58.7 to 61.3 |
| 5 ft 8 in (173 cm) | 68.4 | 67.2 to 69.6 | 63.9 | 62.6 to 64.0 |
| 5 ft 10 in (178 cm) | 73.0 | 70.3 to 75.0 | 68.5 | 66.0 to 68.5 |
| 6 ft 0 in (183 cm) | 77.6 | 73.1 to 80.4 | 73.1 | 69.4 to 73.1 |
| 6 ft 2 in (188 cm) | 82.2 | 75.9 to 85.8 | 77.7 | 72.1 to 77.7 |
| 6 ft 4 in (193 cm) | 86.8 | 78.8 to 91.2 | 82.3 | 74.9 to 82.3 |
At 5 ft 6 in and 5 ft 8 in the four results sit within 2.6 kg of each other for both sexes. At 6 ft 4 in the men's results are 12.4 kg apart, because Hamwi adds 2.7 kg per inch and Miller only 1.41 kg.
Dividing each result by height in meters squared shows the BMI it implies. From 5 ft to 6 ft 4 in, every result lands inside the WHO normal range of 18.5 to 24.9.
The lowest is 19.6 (Devine or Hamwi for a 5 ft woman) and the highest 24.5 (Hamwi for a 6 ft 4 in man).
The formulas drift in different directions as height rises. For men, Devine implies a BMI of 21.5 at 5 ft and 23.3 at 6 ft 4 in, and Hamwi rises from 20.7 to 24.5, so both favor a heavier build in tall men.
Miller's line for men falls from 24.2 to 21.1. Robinson's stays between 22.1 and 22.6 over the whole span.
Shah and colleagues (2006) compared the formulas and published height-weight tables against a BMI of 22. They rated Robinson's formula the best fit for men and found that no formula came close to a BMI of 22 for women.
They concluded that BMI ranges may be more useful in practice than IBW formulas.
When a prescription or drug label gives a dose per kilogram of IBW, the dosage by weight calculator does the multiplication. For a lean-mass estimate from your actual weight, use the lean body mass calculator.
For a personal weight goal, read the formulas against the healthy BMI range. At 5 ft 6 in that range runs from 52.0 to 70.3 kg, and the four formulas place a woman of that height between 58.7 and 61.3 kg, in the middle third of it.
Checked against: 175 cm = 68.8976 in, 8.8976 in over 5 ft; 50 + 2.3 × 8.8976 = 70.4646 etc.; 18.5 × 1.75² and 25 × 1.75²
Checked against: Hand calculation, 4 in over 5 ft: 45.5 + 9.2, 49 + 6.8, 53.1 + 5.44, 45.5 + 8.8; BMI range by exact decimal arithmetic (1.6256 m)
Checked against: Published base weights at 60 in (Pai & Paloucek 2000)
Checked against: Hand calculation with −2 in over 5 ft: 45.5 − 4.6, 49 − 3.4, 53.1 − 2.72, 45.5 − 4.4
Men: 50 kg plus 2.3 kg for each inch over 5 feet. Women: 45.5 kg plus 2.3 kg per inch. A 5 ft 10 in man gets 50 + 2.3 × 10 = 73 kg, and a 5 ft 4 in woman gets 45.5 + 2.3 × 4 = 54.7 kg. B. J. Devine published it in 1974 in a paper on dosing the antibiotic gentamicin.
Mainly drug dosing and ventilator settings. Some drugs, such as aminoglycoside antibiotics, are dosed on IBW or an adjusted weight because they distribute poorly into fat. The ARDS Network's predicted body weight, 50 kg for men or 45.5 kg for women plus 0.91 kg per cm above 152.4 cm, is Devine's formula in centimetres, and lung-protective ventilation sets tidal volume at 6 ml per kg of it.
No formula is clearly better. A 2000 review by Pai and Paloucek traced all of them to the same height-weight tables and concluded that any one may be used to estimate IBW. At 175 cm the four agree within 3.3 kg for men (68.7 to 72.0 kg). They spread further apart at the extremes of height because the men's slopes differ, from 1.41 kg per inch (Miller) to 2.7 kg per inch (Hamwi).
No. IBW is one reference number per height, while a healthy weight is a range. WHO classes a BMI of 18.5 to 24.9 as normal, which at 175 cm spans 56.7 to 76.6 kg, about 20 kg. Any weight in that band counts as normal by the WHO population cut-offs, so an IBW figure is a reference point rather than a personal target.
For information only, not medical advice. These formulas describe populations, not you; talk to a clinician before acting on a result.
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