Slobiq Health / Body and shape / Ideal body weight calculator
Ideal body weight calculator
Enter your sex and height to compare four classic formulas with the healthy BMI range.
These are general estimates, not medical advice, and they do not replace a doctor, dietitian or trainer. If you are pregnant, under 18, have a health condition or take medication, talk to a professional before changing your diet or training.
Calculated in your browser. Nothing you enter is sent or stored.
About this tool: Ideal body weight calculator
Ideal body weight formulas were first developed to dose medicines, and they all start from height. The four here (Hamwi 1964, Devine 1974, Miller 1983 and Robinson 1983) give a bit different answers, so the calculator shows all of them and their average.
No formula knows your build, muscle or age. The range for a healthy BMI of 18.5 to 24.9 is a more useful guide for most people, and it is shown next to the formulas. Treat all of them as a rough orientation, not as a target you must reach.
Formula
Devine, men: 50 kg + 2.3 kg per inch over 5 feet (women 45.5 kg). Robinson: 52 + 1.9 (women 49 + 1.7). Miller: 56.2 + 1.41 (women 53.1 + 1.36). Hamwi: 48 + 2.7 (women 45.5 + 2.2). Healthy range: 18.5 to 24.9 × height in metres squared.
Worked example
A man, 180 cm: Devine 75.0 kg, Robinson 72.6 kg, Miller 71.5 kg, Hamwi 77.3 kg, average 74.1 kg. The healthy BMI range for that height is about 59.9 to 80.7 kg.
Sources and accuracy
- Formulas and sources last reviewed
- Accuracy
- A rough guide only. Typical error of this method is several percentage points or kilograms, so look at the trend over time, not a single number.
Frequently asked questions
Is ideal weight the weight I should aim for?
Not necessarily. It is a statistical orientation. Health depends on fitness, waist size, blood tests and more.
Why do the formulas differ?
They were fitted to different groups of people at different times, so they disagree by a few kilograms.
Does it work for athletes?
Not well. Muscular people can weigh more than any formula suggests and still be healthy.