Ideal Weight Calculator
Choose your sex and enter your height to compare ideal body weight from four well-known medical formulas side by side, together with the healthy weight range for your height based on BMI.
Formula comparison
| Formula | Equation (men) | Ideal weight |
|---|
These formulas estimate a healthy body weight from height and sex only. They do not account for muscle mass, frame size or age, so use them as a guide alongside the BMI range and advice from a health professional.
How to use the Ideal Weight Calculator
- Choose male or female, because each formula uses different constants for men and women.
- Enter your height in centimetres, or switch to feet and inches.
- Pick kg or lb for the results, and optionally enter your current weight to compare.
- Press Calculate (results also update as you type) to see each formula, the average and the healthy BMI range.
- Copy the results to keep them or share them with your doctor or coach.
Ideal body weight formulas
| Formula | Men | Women |
|---|---|---|
| Robinson (1983) | 52 kg + 1.9 kg per inch over 5 ft | 49 kg + 1.7 kg per inch over 5 ft |
| Miller (1983) | 56.2 kg + 1.41 kg per inch over 5 ft | 53.1 kg + 1.36 kg per inch over 5 ft |
| Devine (1974) | 50 kg + 2.3 kg per inch over 5 ft | 45.5 kg + 2.3 kg per inch over 5 ft |
| Hamwi (1964) | 48 kg + 2.7 kg per inch over 5 ft | 45.5 kg + 2.2 kg per inch over 5 ft |
To use a height in centimetres, divide by 2.54 to get inches, then subtract 60. For example 180 cm = 70.87 in, which is 10.87 inches over 5 ft.
Worked example: a man 180 cm tall
- Robinson: 52 + 1.9 × 10.87 = 72.6 kg
- Miller: 56.2 + 1.41 × 10.87 = 71.5 kg
- Devine: 50 + 2.3 × 10.87 = 75.0 kg
- Hamwi: 48 + 2.7 × 10.87 = 77.3 kg
- Healthy BMI range: 18.5 × 1.8² to 24.9 × 1.8² = 59.9 to 80.7 kg
Ideal weight chart (Devine formula and BMI range)
| Height | Men (Devine) | Women (Devine) | Healthy BMI range |
|---|---|---|---|
| 5 ft 0 in (152 cm) | 50.0 kg (110 lb) | 45.5 kg (100 lb) | 43.0 – 57.8 kg |
| 5 ft 2 in (157 cm) | 54.6 kg (120 lb) | 50.1 kg (110 lb) | 45.9 – 61.8 kg |
| 5 ft 4 in (163 cm) | 59.2 kg (131 lb) | 54.7 kg (121 lb) | 48.9 – 65.8 kg |
| 5 ft 6 in (168 cm) | 63.8 kg (141 lb) | 59.3 kg (131 lb) | 52.0 – 70.0 kg |
| 5 ft 8 in (173 cm) | 68.4 kg (151 lb) | 63.9 kg (141 lb) | 55.2 – 74.3 kg |
| 5 ft 10 in (178 cm) | 73.0 kg (161 lb) | 68.5 kg (151 lb) | 58.5 – 78.7 kg |
| 6 ft 0 in (183 cm) | 77.6 kg (171 lb) | 73.1 kg (161 lb) | 61.9 – 83.3 kg |
| 6 ft 2 in (188 cm) | 82.2 kg (181 lb) | 77.7 kg (171 lb) | 65.4 – 88.0 kg |
| 6 ft 4 in (193 cm) | 86.8 kg (191 lb) | 82.3 kg (181 lb) | 68.9 – 92.8 kg |
Frequently asked questions
What is ideal body weight?
Ideal body weight (IBW) is an estimate of a healthy weight for your height and sex. The formulas were first developed to calculate medication doses, and are now widely used as a rough guide to a healthy target weight.
Which ideal weight formula is the most accurate?
None is perfect. Devine (1974) is the most widely used in medicine, Robinson and Miller (1983) were later refinements based on population data, and Hamwi (1964) is an older rule of thumb. Comparing all four, together with the BMI range, gives a more balanced picture than any single number.
What are the formulas?
For men: Robinson 52 kg + 1.9 kg, Miller 56.2 kg + 1.41 kg, Devine 50 kg + 2.3 kg and Hamwi 48 kg + 2.7 kg per inch over 5 feet. For women: Robinson 49 kg + 1.7 kg, Miller 53.1 kg + 1.36 kg, Devine 45.5 kg + 2.3 kg and Hamwi 45.5 kg + 2.2 kg per inch over 5 feet.
What if I am shorter than 5 feet?
The formulas were built for heights of 5 ft (152.4 cm) and above. For shorter heights this calculator subtracts the same per-inch amount for each inch under 5 ft, which is a common clinical approach, but the results are less reliable, so the BMI range is a better guide.
What is the healthy BMI weight range?
It is the range of weights that give a BMI between 18.5 and 24.9 at your height: 18.5 × height² to 24.9 × height², with height in metres. For someone 175 cm tall that is about 56.7 to 76.3 kg.
Does ideal weight account for muscle?
No. These formulas use only height and sex, so athletes and people with a lot of muscle can be healthy well above them. Waist size, body fat percentage and medical advice give a fuller picture.
Should I aim for exactly my ideal weight?
Not necessarily. Treat the results as a broad target zone rather than a precise goal. Being anywhere within the healthy BMI range is generally associated with lower health risks for most adults.