Ideal Weight Calculator: Ideal Body Weight Calculator for Your Height
Ideal body weight calculator using the Devine, Robinson, Miller and Hamwi formulas, with the spread between them and the healthy BMI range for your height.
Results
Assumptions and formula
Each of the four formulas is a base weight at five feet plus a fixed increment per inch above it, published separately for men and women: Devine (1974), Hamwi (1964), Robinson (1983) and Miller (1983). Only Hamwi takes a frame-size adjustment, ±10%. The healthy range shown beside them is BMI 18.5 to 24.9 at the entered height, and the gap to it is reported when you give your current weight.
None of the four was derived from health outcomes. Devine’s appeared in a 1974 pharmacy note as a way to estimate gentamicin doses and is still used for drug dosing; the others are refits of its shape against insurance height–weight tables. They also return a single number per height, which no evidence supports — the weight range associated with the lowest risk spans roughly 14 kg or 30 lb. BMI has its own limits: it does not distinguish muscle from fat, and several bodies apply lower thresholds for South Asian and East Asian populations.
Worked example
At exactly five feet the formulas return their base weights for a man: Devine 50 kg, Robinson 52, Miller 56.2, Hamwi 48. At six feet they have separated to 77.6, 74.8, 73.1 and 80.4 — over 7 kg apart for the same height. The BMI 18.5–24.9 range at 180 cm is 59.9 to 80.7 kg, a span of nearly 21 kg, and that range is the answer to the question most readers are really asking.
Ideal weight chart by height, men and women
The lowest and highest of the four formulas at each height, with the BMI 18.5–24.9 range beside them. The formulas give men a higher figure than women at the same height; the BMI range is the same for both. Enter your own height above for all four values.
| Height | Men, four formulas | Women, four formulas | Healthy BMI range |
|---|---|---|---|
| 4 ft 10 in (147 cm) | Formulas start at 5 ft | Formulas start at 5 ft | 89 lb (40 kg) – 119 lb (54 kg) |
| 4 ft 11 in (150 cm) | Formulas start at 5 ft | Formulas start at 5 ft | 92 lb (42 kg) – 123 lb (56 kg) |
| 5 ft 0 in (152 cm) | 106 lb (48 kg) – 124 lb (56 kg) | 100 lb (45 kg) – 117 lb (53 kg) | 95 lb (43 kg) – 128 lb (58 kg) |
| 5 ft 1 in (155 cm) | 112 lb (51 kg) – 127 lb (58 kg) | 105 lb (48 kg) – 120 lb (55 kg) | 98 lb (44 kg) – 132 lb (60 kg) |
| 5 ft 2 in (157 cm) | 118 lb (53 kg) – 130 lb (59 kg) | 110 lb (50 kg) – 123 lb (56 kg) | 101 lb (46 kg) – 136 lb (62 kg) |
| 5 ft 3 in (160 cm) | 124 lb (56 kg) – 133 lb (60 kg) | 115 lb (52 kg) – 126 lb (57 kg) | 104 lb (47 kg) – 141 lb (64 kg) |
| 5 ft 4 in (163 cm) | 130 lb (59 kg) – 136 lb (62 kg) | 120 lb (54 kg) – 129 lb (59 kg) | 108 lb (49 kg) – 145 lb (66 kg) |
| 5 ft 5 in (165 cm) | 136 lb (62 kg) – 140 lb (63 kg) | 125 lb (57 kg) – 132 lb (60 kg) | 111 lb (50 kg) – 150 lb (68 kg) |
| 5 ft 6 in (168 cm) | 140 lb (63 kg) – 143 lb (65 kg) | 129 lb (59 kg) – 135 lb (61 kg) | 115 lb (52 kg) – 154 lb (70 kg) |
| 5 ft 7 in (170 cm) | 144 lb (65 kg) – 148 lb (67 kg) | 134 lb (61 kg) – 138 lb (63 kg) | 118 lb (54 kg) – 159 lb (72 kg) |
| 5 ft 8 in (173 cm) | 148 lb (67 kg) – 153 lb (70 kg) | 138 lb (63 kg) – 141 lb (64 kg) | 122 lb (55 kg) – 164 lb (74 kg) |
| 5 ft 9 in (175 cm) | 152 lb (69 kg) – 159 lb (72 kg) | 142 lb (64 kg) – 146 lb (66 kg) | 125 lb (57 kg) – 169 lb (76 kg) |
| 5 ft 10 in (178 cm) | 155 lb (70 kg) – 165 lb (75 kg) | 146 lb (66 kg) – 151 lb (68 kg) | 129 lb (58 kg) – 174 lb (79 kg) |
| 5 ft 11 in (180 cm) | 158 lb (72 kg) – 171 lb (78 kg) | 149 lb (68 kg) – 156 lb (71 kg) | 133 lb (60 kg) – 179 lb (81 kg) |
| 6 ft 0 in (183 cm) | 161 lb (73 kg) – 177 lb (80 kg) | 153 lb (69 kg) – 161 lb (73 kg) | 136 lb (62 kg) – 184 lb (83 kg) |
| 6 ft 1 in (185 cm) | 164 lb (74 kg) – 183 lb (83 kg) | 156 lb (71 kg) – 166 lb (75 kg) | 140 lb (64 kg) – 189 lb (86 kg) |
| 6 ft 2 in (188 cm) | 167 lb (76 kg) – 189 lb (86 kg) | 159 lb (72 kg) – 171 lb (78 kg) | 144 lb (65 kg) – 194 lb (88 kg) |
| 6 ft 3 in (191 cm) | 171 lb (77 kg) – 195 lb (88 kg) | 162 lb (73 kg) – 176 lb (80 kg) | 148 lb (67 kg) – 199 lb (90 kg) |
| 6 ft 4 in (193 cm) | 174 lb (79 kg) – 201 lb (91 kg) | 165 lb (75 kg) – 181 lb (82 kg) | 152 lb (69 kg) – 205 lb (93 kg) |
| 6 ft 5 in (196 cm) | 177 lb (80 kg) – 207 lb (94 kg) | 168 lb (76 kg) – 187 lb (85 kg) | 156 lb (71 kg) – 210 lb (95 kg) |
| 6 ft 6 in (198 cm) | 180 lb (82 kg) – 213 lb (97 kg) | 171 lb (78 kg) – 192 lb (87 kg) | 160 lb (73 kg) – 216 lb (98 kg) |
Frequently asked questions
Where do the ideal weight formulas come from?
Not from health research. Devine’s equation appeared in a 1974 pharmacy note as a convenient way to estimate doses of gentamicin, and it remains in drug references for exactly that. Hamwi’s came from 1964 diabetic diet work; Robinson’s and Miller’s are 1983 refits against insurance-company height–weight tables. None was tested against mortality, illness or fitness, which is why "ideal" is doing a lot of work in the name. To find or figure out your ideal body weight, it compares the main ideal-weight formulas side by side for your height and sex. The table on this page doubles as a chart of weight according to height: find your height to read the ideal weight range for men and women and the healthy-BMI weight range, a weight as per height chart in feet and centimetres.
Why do the four formulas disagree?
Because each fitted a different sample with a different slope. They all take a base weight at 5 feet and add a fixed amount per inch — Hamwi adds 2.7 kg per inch for men, Miller only 1.41 — so they separate as height rises. At 6 feet the four can be 10 kg apart for the same man. Four confident, incompatible answers to the same question is a reason to treat all of them as rough.
What should I weigh, then?
A range rather than a number. The BMI 18.5–24.9 band at your height is the usual answer, and it is deliberately wide — about 14 kg or 30 lb for a typical adult — because that is what the outcome data supports. Where you sit inside it depends on build, muscle and history. Waist circumference adds information BMI misses: over 94 cm (37 in) for men or 80 cm (31.5 in) for women marks raised risk regardless of BMI.
Is BMI a better measure than ideal body weight?
For this question, yes — it gives a range from population outcome data rather than a point from a dosing rule. But it has its own limits: it cannot tell muscle from fat, so it misclassifies muscular people as overweight, and it reads differently across ethnic groups. WHO and several national bodies apply lower thresholds for South Asian and East Asian populations, where cardiometabolic risk rises at a lower BMI.
What is frame size and does it matter?
A rough classification of skeletal build, usually from wrist circumference relative to height. Only the Hamwi formula uses it, adjusting by ±10%. It is a crude proxy — bone mass varies less between adults than the ±10% implies — and it cannot rescue a formula that was not measuring health in the first place. Treat it as a footnote, not a correction.
How much should I weigh for my height?
Somewhere in a range, not at a single number. An IBW calculator using the Devine formula gives about 66 kg for a 170 cm man and 61.5 kg for a woman of the same height, but those formulas were built for drug dosing, not health, and the four classic ones disagree by several kilograms at any height. The evidence-based answer to how much you should weigh is the BMI 18.5 to 24.9 band, which at 170 cm runs from 53.5 to 72 kg. This page shows the formula values and that range side by side so you can see how far apart they are.
What is the ideal body weight formula, and is there an ideal weight chart?
The most used ideal body weight formula is Devine (1974): 50 kg plus 2.3 kg for every inch over five feet for men, 45.5 kg plus 2.3 kg per inch for women. A Devine formula calculator is what hospital dosing tools run, which is the only setting the formula was designed for. An ideal weight chart lays the same formulas out by height, and reading one shows the problem: at every height the four classic formulas disagree by several kilograms, and none matches the ideal weight for height that health data supports, which is a range. This page gives the formula values and the range together so you can see both.
What is adjusted body weight?
A weight between your ideal and your actual weight that clinicians use to dose some medicines when a patient weighs more than the ideal: Devine ideal weight plus 0.4 times the difference. Enter your current weight and the page shows it whenever you weigh more than the Devine figure. It is a dosing convention, not a target.
Sources
Sources reviewed 13 September 2026: checked against their current editions on that date.
- Devine BJ. Gentamicin therapy. Drug Intelligence and Clinical Pharmacy, 1974; 8: 650–655.
- Robinson JD, Lupkiewicz SM, Palenik L, Lopez LM, Ariet M. Determination of ideal body weight for drug dosage calculations. American Journal of Hospital Pharmacy, 1983; 40(6): 1016–1019.
- Pai MP, Paloucek FP. The origin of the "ideal" body weight equations. Annals of Pharmacotherapy, 2000; 34(9): 1066–1069.
- World Health Organization. Obesity: preventing and managing the global epidemic. WHO Technical Report Series 894, 2000; and WHO expert consultation on BMI cut-off points for Asian populations, Lancet 2004; 363: 157–163.
This page is an educational estimate and is not medical advice. Follow individual guidance from your clinician.