Ideal Weight Calculator
Estimate a healthy weight range from your height using the healthy-BMI band plus the classic Devine, Robinson, Miller, and Hamwi formulas.
A healthy weight for 178 cm spans this range — there is no single ideal number.
There is no single ideal weight — aim for a healthy range. For a 178 cm adult, the healthy-BMI band (18.5–24.9) works out to roughly 59–79 kg. Classic formulas add a point estimate on top: the Devine formula puts a 178 cm man near 73 kg. Treat the range, not one number, as your target.
Why a range, not one number
“Ideal body weight” is a useful shorthand, but no formula can name the single correct weight for a person. Frame size, muscle mass, and body composition all shift what is healthy for a given height. The most defensible answer is a range: the weights that put your body mass index inside the healthy band of 18.5 to 24.9. This calculator leads with that range, then shows four classic point-estimate formulas for context.
The named formulas — Devine, Robinson, Miller, and Hamwi — were built decades ago from population data, mostly to help dose medication by body size. They take your height in inches, subtract 60 (5 feet), and add a fixed amount per inch above that. They are quick reference points, not a verdict.
The BMI band gives a range in kg. The named formulas (Devine, Robinson, Miller, Hamwi) add a single point estimate from height in inches above 60.
Worked example: male, 178 cm
Convert height, apply the healthy-BMI band, then compare with a named formula:
- 1 Convert height to metres and inches. 178 cm = 1.78 m, and 178 ÷ 2.54 ≈ 70.08 in (about 5 ft 10 in).
- 2 Square the height in metres. 1.78² = 3.1684 m².
- 3 Apply the healthy-BMI band. 18.5 × 3.1684 ≈ 58.6 kg and 24.9 × 3.1684 ≈ 78.9 kg, so the healthy range is about 59–79 kg.
- 4 Add a named formula for context. Devine (men): 50 + 2.3·(70.08 − 60) = 50 + 2.3·10.08 ≈ 73.2 kg — comfortably inside the range.
- 5 Read the range, not one number. Anywhere in the 59–79 kg band is a healthy weight for this height; the formula estimate is just one point within it.
Classic ideal-weight formulas
Each uses height in inches; (in − 60) is inches above 5 feet. Constants differ by sex.
| Formula | Men (kg) | Women (kg) |
|---|---|---|
| Devine (1974) | 50 + 2.3·(in − 60) | 45.5 + 2.3·(in − 60) |
| Robinson (1983) | 52 + 1.9·(in − 60) | 49 + 1.7·(in − 60) |
| Miller (1983) | 56.2 + 1.41·(in − 60) | 53.1 + 1.36·(in − 60) |
| Hamwi (1964) | 48.0 + 2.7·(in − 60) | 45.5 + 2.2·(in − 60) |
How to read the estimate
The four formulas usually land within a few kilograms of one another and inside the healthy-BMI range, which is why they are handy sanity checks. But they share real limits. They are dated population estimates that assume an “average” build: they ignore muscle mass, bone structure, and body-fat distribution entirely, so a lean, muscular athlete can sit well above their formula weight while being perfectly healthy. They also break down at short heights — because they subtract 60 inches, they are only meaningful above 5 feet, and below that they collapse toward the base constant.
This tool is for general information, not medical advice. Ideal-weight formulas and BMI are screening estimates, not diagnoses; talk to a qualified professional before making significant changes to your weight or diet.