Ideal weight calculator

Find your ideal weight range using multiple established formulas, in kg or lbs.

Devine formula
BMI range (18.5–25)
Robinson formula

How ideal weight is calculated

This calculator uses the Devine formula, one of the most widely cited methods in clinical settings. The formulas are:

Men: Ideal weight (kg) = 50 + 2.3 × (height in inches − 60)
Women: Ideal weight (kg) = 45.5 + 2.3 × (height in inches − 60)

For example, a man who is 175 cm (5'9") tall: 50 + 2.3 × (69 − 60) = 50 + 20.7 = 70.7 kg. Alternative formulas include Robinson (1983), Miller (1983), and Hamwi (1964) — all produce slightly different values. The calculator shows a healthy weight range (±10%) to reflect biological variation. No single number suits every individual: bone density, muscle mass, and body frame all affect what's genuinely healthy for you. Use ideal weight alongside BMI, waist circumference, and a doctor's assessment rather than as a standalone target.

Frequently asked questions

What formula is used to calculate ideal weight?

This calculator uses the Devine formula (1974): for men, 50 kg + 2.3 kg per inch over 5 feet; for women, 45.5 kg + 2.3 kg per inch over 5 feet. It was originally developed for pharmaceutical dosing but is widely used as a general reference.

Is ideal weight the same as healthy weight?

Not exactly. 'Ideal weight' is a formula-derived estimate. 'Healthy weight' is a range based on BMI (18.5–24.9) or clinical assessment. The Devine formula gives a single target number, but a ±10% range is more realistic for diverse body types.

Does body frame size affect ideal weight?

Yes. People with a larger bone frame naturally weigh more at the same height. The standard formula doesn't account for frame size. A simple self-test: wrap your thumb and middle finger around your wrist — if they overlap, small frame; if they meet, medium; if they don't reach, large frame.

How is ideal weight different from BMI?

BMI gives a score from weight and height that maps to weight categories (underweight, normal, overweight, obese). Ideal weight gives a target weight in kg/lbs for a given height. They're related concepts but use different approaches and serve different purposes.

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