Ideal Weight Calculator: Robinson, Miller, Devine, Hamwi
Estimate your ideal body weight by the Robinson, Miller, Devine and Hamwi formulas side by side, with the healthy weight range for your height from BMI 18.5 to 24.9. Centimetres or feet and inches, results in kg and lb. Nothing is uploaded.
Enter your height to see your ideal and healthy weight.
About the Ideal Weight Calculator
The Ideal Weight Calculator estimates an adult's ideal body weight from height and sex with four published formulas, shown side by side: Robinson (1983), Miller (1983), Devine (1974) and Hamwi (1964). Below them it shows the healthy weight range for the same height, the weights that give a body mass index (BMI) between 18.5 and 24.9. Enter your height in centimetres or in feet and inches; every result is shown in both kilograms and pounds. If you add your current weight, the calculator also says how far it is from the healthy range.
The formulas disagree by a few kilograms because each was fitted to a different group of people for a different purpose. Seeing them together, next to the BMI range, gives a fairer picture than any single number.
This is an estimate, not medical advice. None of these formulas accounts for muscle, body frame, age or ethnicity, so talk to a doctor or a registered dietitian about the weight that is right for you.
How to use it
Steps
- Choose Metric or US customary units.
- Choose Male or Female, since each formula has a version for men and one for women.
- Enter your height. Optionally enter your current weight to compare it with the healthy range.
- Read the four formula results and the healthy weight range.
The formulas
Each formula starts from a base weight at 5 feet (152.4 cm) and adds a fixed amount for every inch above it. With as the height in inches over 60:
Heights under 5 feet
The formulas were built for adults of 5 feet and taller, and subtracting weight for each inch below that gives results the authors never tested. Below 152.4 cm the calculator therefore shows only the healthy BMI range, which works for any adult height.
Healthy weight range
The range is the weight at a BMI of 18.5 and of 24.9 for your height: weight equals BMI times height in metres squared. At 175 cm that is 56.7 to 76.3 kg. The cut-offs come from the World Health Organization.
Worked example
A man 6 feet tall (182.88 cm) is 12 inches over 5 feet. Robinson gives 52 + 1.9 × 12 = 74.8 kg, Miller 73.1 kg, Devine 77.6 kg and Hamwi 80.4 kg. His healthy weight range is 61.9 to 83.3 kg.
Privacy
Nothing is uploaded. The calculation runs in your browser, and your height and weight never leave your device.
Related tools
Check your current BMI and WHO class with the BMI Calculator, or focus on the BMI range alone with the Healthy Weight Calculator. Convert kilograms and pounds with the Mass Converter and centimetres to feet with the Length Converter.
Sources
- 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.
- Miller DR, Carlson JD, Lloyd BJ, Day BJ. Determining ideal body weight (and mass). American Journal of Hospital Pharmacy 1983;40(10):1622–1625.
- Devine BJ. Gentamicin therapy. Drug Intelligence and Clinical Pharmacy 1974;8:650–655.
- Hamwi GJ. Therapy: changing dietary concepts. In: Diabetes Mellitus: Diagnosis and Treatment, vol. 1. American Diabetes Association, 1964:73–78.
- World Health Organization. A healthy lifestyle: WHO recommendations, BMI classification for adults.
Open-source credits
The calculations are implemented in-house in TypeScript, with no third-party library. They follow the published Robinson, Miller, Devine and Hamwi formulas and the WHO adult BMI cut-offs listed above.
Frequently asked questions
Which ideal weight formula is the most accurate?
None is clearly best. Devine (1974) was written for drug dosing and is still used for that in hospitals; Robinson and Miller (1983) were later fitted to height and weight tables, and Hamwi (1964) is a rule of thumb from diabetes care. They differ by a few kilograms, so it helps to look at them together with the healthy BMI range.
Why are there no formula results for my height?
All four formulas add weight for each inch over 5 feet (152.4 cm) and were never fitted to shorter adults. Below that height the calculator shows only the healthy weight range from BMI 18.5 to 24.9, which works for any adult height.
What is the healthy weight range?
It is the range of weights that gives a body mass index from 18.5 to 24.9 at your height, the World Health Organization's normal range. The weight at a given BMI is the BMI times your height in metres squared.
Does the calculator work for children?
No. The formulas and the BMI cut-offs are for adults. Children and teenagers are assessed with growth charts for their age and sex, so ask a doctor or health visitor about a child's weight.
Is my information stored or sent anywhere?
No. Everything is calculated in your browser. Your height and weight are never sent anywhere and are gone when you close the page.