Ideal weight calculator

How to find your ideal weight

1. Select your sex. The Hamwi and Devine formulas differ by sex.
2. Choose your height unit: centimetres or feet and inches.
3. Enter your height.
4. View your ideal weight range from all three formulas side by side. The WHO BMI range is the most evidence-based.

Common uses

• Setting a realistic weight loss goal based on your height, then finding the daily calorie target to get there
• Understanding where your current weight sits relative to established norms alongside your BMI
• Comparing different formula estimates to get a consensus range

Technical specification

• Algorithm or formula: Hamwi (1964) men: 48 kg + 2.7 kg per inch over 5 ft; women: 45.5 kg + 2.2 kg per inch over 5 ft. Devine (1974) men: 50 kg + 2.3 kg per inch over 5 ft; women: 45.5 kg + 2.3 kg per inch over 5 ft. WHO range (Technical Report Series 894, 2000): weight at BMI 18.5 and 24.9 for the given height.
• Browser API or library: Pure JavaScript arithmetic. No external library.
• Input limits: Height 50 to 272 cm (1 ft 8 in to 8 ft 11 in, with inches below 12). Values outside this range show a hint instead of a result. Below 5 ft, Hamwi and Devine give their 5 ft base weight. Sex toggle (Hamwi and Devine only).
• Output: Three side-by-side estimates: Hamwi ideal weight, Devine ideal weight, and WHO healthy-weight range.
• Known limitations: Hamwi and Devine are clinical rules of thumb, from diabetes diet planning (Hamwi) and drug dosing (Devine), not body-composition assessment. None of the three formulas account for muscle mass or frame size.

Frequently asked questions

What is the ideal weight for my height?

At 170 cm (about 5 ft 7 in), the WHO healthy BMI range of 18.5 to 24.9 works out to 53.5 to 72.0 kg (117.9 to 158.6 lbs). At the same height, Hamwi gives 66.7 kg for a man and 60.7 kg for a woman, and Devine gives 65.9 kg and 61.4 kg. Results are estimates for informational purposes only.

What is an ideal body weight?

Ideal body weight is a weight range associated with reduced risk of weight-related health conditions. It is a range rather than a single number. In this calculator the WHO BMI range (18.5–24.9) depends only on your height and gives the most evidence-based estimate, while the Hamwi and Devine values also depend on sex. None of the three measure body composition.

Do I need an account to use this calculator?

The calculator works without an account. Enter your height and all three formula results appear immediately. All calculations run in your browser. Our servers are not involved at any point.

Why are three formulas shown instead of one?

Different formulas are used in different contexts. Hamwi and Devine are older clinical rules of thumb: Hamwi comes from diabetes diet planning and Devine from drug dosing. The WHO BMI range is based on epidemiological data and is the most broadly applicable. Showing all three lets you see the consensus and the spread.