Ideal Weight Calculator
Enter your sex and height to see four classic ideal body weight formulas side by side with the weight range that gives a healthy BMI. The formulas are historical reference points, not goals, so the page explains where they came from and what they leave out.
Ideal weight calculator
How to use the ideal weight calculator
- Choose sex and enter height. The formulas were written for adults and use height and sex only. Enter your height in feet and inches or centimetres.
- Compare the four formulas. Devine, Robinson, Miller and Hamwi give slightly different answers; the headline shows the range between them.
- Compare with the BMI range. The healthy BMI range (18.5 to 24.9) is much wider and is the more widely used screening reference.
- Talk about a goal with your doctor. Frame, muscle, age and health all matter, so a personal target is best set with a clinician.
Not medical advice. This calculator gives general information from published formulas and is not a diagnosis, treatment or substitute for a doctor, midwife or registered dietitian. Do not use these numbers as a target if you have had an eating disorder or are underweight; speak to a doctor.
The four formulas
Height is in inches over 5 feet (60 in).
| Formula | Men | Women |
|---|---|---|
| Hamwi (1964) | 106 lb + 6 lb per inch | 100 lb + 5 lb per inch |
| Devine (1974) | 50 kg + 2.3 kg per inch | 45.5 kg + 2.3 kg per inch |
| Robinson (1983) | 52 kg + 1.9 kg per inch | 49 kg + 1.7 kg per inch |
| Miller (1983) | 56.2 kg + 1.41 kg per inch | 53.1 kg + 1.36 kg per inch |
Worked examples
A man 5 ft 10 in. Devine 161 lb, Robinson 157 lb, Miller 155 lb, Hamwi 166 lb. The healthy BMI range at this height is 129 to 174 lb, which includes all four.
A woman 5 ft 5 in. Devine 126 lb, Robinson 127 lb, Miller 132 lb, Hamwi 125 lb, against a BMI range of 111 to 150 lb.
Why formulas are only reference points
They ignore age, frame size, muscle, bone density and ancestry, and the 1960s–80s populations they came from differ from today’s. Use them as one reference among several, and see the BMI calculator for the screening range, the body fat calculator for composition and the waist ratio calculator for fat distribution.
Setting a goal
If you and your doctor decide weight loss would help, the weight loss calculator shows how long a safe pace takes and never aims below a BMI of 18.5.
Frequently asked questions
What is my ideal weight?
There is no single answer. Four formulas based on height and sex give a spread of about 10 lb at average height, and the healthy BMI range at the same height can span 40 lb or more.
Where did the ideal weight formulas come from?
Hamwi proposed his rule in 1964 and Devine adapted it in 1974 for drug dosing. Robinson and Miller published new versions in 1983. A review by Pai and Paloucek traces how they started as dosing and insurance tools, not health targets.
Which formula is best?
None is validated as a health target. They are mostly used in clinical dosing. For a health reference, the BMI range recommended by the CDC and NHS is more commonly used.
Why does the BMI range look so different?
The formulas give one number for a typical frame. BMI allows a range because healthy bodies vary in frame, muscle and bone. At 5 ft 10 in a man's BMI range is 129 to 174 lb.
Do the formulas work for short people?
They are built from 5 feet upward and are not reliable below 4 ft 6 in, where this tool does not show them. The BMI calculator covers all adult heights.
Should I aim for my ideal weight?
Not necessarily. Muscular people, older adults and people of different ancestry may be healthy at different weights. NHS advice is that losing 5 to 10% of weight can improve health if you have overweight or obesity.
Is it safe to be below my ideal weight?
Being underweight (BMI under 18.5) has its own health risks. If you are underweight or losing weight unintentionally, see your doctor.
Related calculators
BMI Calculator
BMI, category and healthy weight range for adults.
Weight Loss Calculator (Calorie Deficit)
Daily calories, deficit and a realistic goal date for a weight goal.
Body Fat Calculator (U.S. Navy Method)
Body fat % from height, neck, waist (and hip) using the Navy formula.
Waist-to-Hip & Waist-to-Height Ratio Calculator
Waist-to-height and waist-to-hip ratios with NICE and WHO bands.
Sources and references
About this calculator
Written and maintained by Rashid Mehmood, founder of CalcTen. The formulas are unit-tested against hand-worked examples, and the content is reviewed whenever product sizes or guidance change. Last updated 14 November 2026. See our editorial policy.
This calculator gives general information and is not medical advice, diagnosis or treatment. Results are estimates based on population averages. Talk to a doctor or other qualified health professional about your own situation. Read the disclaimer.