MyAgeCalc

Ideal weight calculator

Four medical formulas side by side, plus the healthy BMI range for your height. A 5′6″ woman, for example, comes out at roughly 129–135 lb by formula and 115–154 lb by BMI.

Height
Ideal weight at 5′6″female
131

lb: the average of four formulas. Healthy BMI range: 115 lb – 154 lb.

FormulaIdeal weight
Robinson (1983)130 lb
Miller (1983)135 lb
Devine (1974)131 lb
Hamwi (1964)129 lb
Healthy BMI 18.5–24.9115 lb – 154 lb

Your BMI now: 24.2 (healthy weight)

Estimates for general information, not medical advice. Talk to a doctor or dietitian about your own health.

Where the formulas come from

“Ideal body weight” started as a dosing tool. In 1974 the pharmacologist B. J. Devine proposed 50 kg for a 5-foot man plus 2.3 kg per extra inch, so that drug doses could be scaled to a lean body rather than total weight. Hamwi's 1964 rule of thumb was similar; Robinson and Miller re-fitted the slopes to life-insurance height-weight tables in 1983.

All four say nothing about muscle, frame or age. That's why we show the healthy BMI range next to them: it is wider, it is what the WHO and CDC use for adults, and it is a better guide for someone simply asking “am I in a reasonable range?”.

For a sense of where your weight sits rather than what it “should” be, pair this with the waist-to-hip ratio and lean body mass calculators.

Ideal weight chart

Devine formula and healthy-BMI range, by height.

HeightWomenMenHealthy BMI range
4′10″ 147 cm90 lb100 lb89 lb–119 lb
4′11″ 150 cm95 lb105 lb92 lb–123 lb
5′0″ 152 cm100 lb110 lb95 lb–127 lb
5′1″ 155 cm105 lb115 lb98 lb–132 lb
5′2″ 157 cm110 lb120 lb101 lb–136 lb
5′3″ 160 cm116 lb125 lb104 lb–141 lb
5′4″ 163 cm121 lb131 lb108 lb–145 lb
5′5″ 165 cm126 lb136 lb111 lb–150 lb
5′6″ 168 cm131 lb141 lb115 lb–154 lb
5′7″ 170 cm136 lb146 lb118 lb–159 lb
5′8″ 173 cm141 lb151 lb122 lb–164 lb
5′9″ 175 cm146 lb156 lb125 lb–169 lb
5′10″ 178 cm151 lb161 lb129 lb–174 lb
5′11″ 180 cm156 lb166 lb133 lb–179 lb
6′0″ 183 cm161 lb171 lb136 lb–184 lb
6′1″ 185 cm166 lb176 lb140 lb–189 lb
6′2″ 188 cm171 lb181 lb144 lb–194 lb
6′3″ 191 cm176 lb186 lb148 lb–199 lb
6′4″ 193 cm181 lb191 lb152 lb–205 lb
6′5″ 196 cm187 lb196 lb156 lb–210 lb
6′6″ 198 cm192 lb202 lb160 lb–215 lb

Questions

What is the ideal weight for my height?

There is no single number. The four classic formulas (Robinson, Miller, Devine, Hamwi) give a point estimate from height and sex, and they usually land within about 10 lb (4–5 kg) of each other. A broader and more widely used guide is the weight range that keeps your BMI between 18.5 and 24.9.

Does age change my ideal weight?

None of the ideal-body-weight formulas use age; they were built from height and sex alone. Ageing does change body composition (less muscle, more fat at the same weight), and some research suggests a BMI slightly above 25 is not linked to higher mortality in people over 65, so older adults should discuss targets with a doctor rather than rely on a formula.

Is 5′2″ and 120 pounds underweight?

No. 120 lb at 5′2″ is a BMI of about 21.9, which is in the healthy 18.5–24.9 range. The healthy-BMI range for that height is roughly 101–136 lb; the Devine formula gives about 110 lb for a woman.

Which ideal weight formula is the most accurate?

None is accurate for an individual. Devine (1974) is the one most used in medicine, mainly to dose drugs; Robinson and Miller (1983) were later refits of the same idea. Treat the spread between them as a rough band, not a target.

How do I calculate ideal body weight by hand?

Devine: start with 50 kg for men or 45.5 kg for women at 5 feet, then add 2.3 kg for every inch above 5 feet. A 5′10″ man: 50 + 2.3 × 10 = 73 kg (161 lb).

Why does my ideal weight look too low for my build?

The formulas ignore muscle and frame size. Athletes and people with a large frame are often healthy well above the formula figure. Waist-to-hip ratio and lean body mass give a better picture of composition.

Sources

  • Devine BJ. Gentamicin therapy. Drug Intell Clin Pharm, 1974.
  • Robinson JD et al. Determination of ideal body weight for drug dosage calculations. Am J Hosp Pharm, 1983. Miller DR et al., same journal, 1983.
  • World Health Organization and CDC adult BMI categories (18.5–24.9 healthy).