🎯 Ideal Weight Calculator

How Ideal Weight Is Calculated — and Its Limitations

This calculator uses the Devine formula, one of the most commonly cited ideal body weight equations in medical and clinical settings. For men: Ideal weight (kg) = 50 + 2.3 × (height in inches above 5 feet). For women: Ideal weight (kg) = 45.5 + 2.3 × (height in inches above 5 feet). The Devine formula was developed in the 1970s primarily for medication dosing purposes — not as an aesthetic or fitness standard.

The concept of a single "ideal weight" is widely recognised by health professionals as an oversimplification. Two people with exactly the same height can have very different healthy weights based on body frame size, muscle mass, bone density, and body composition. A heavily muscled person may weigh 20 kg more than the formula suggests while having a lower body fat percentage than someone at the "ideal" weight with low muscle mass.

More useful metrics include body fat percentage (measured with skinfold callipers, DEXA scan, or bioelectrical impedance), waist circumference (health risk rises above 94 cm for men and 80 cm for women), and waist-to-height ratio (a waist circumference below half your height is a good general target). These measures capture metabolic health more accurately than body weight alone.

BMI (Body Mass Index) is the other common population-level weight benchmark. Unlike the Devine formula, BMI is based on weight divided by height squared. Both have the same limitation — neither accounts for body composition. Use them as a rough reference point rather than a personal health target.

The most important thing is not a specific number on the scale, but whether your metabolic markers (blood pressure, blood glucose, cholesterol, triglycerides) are in healthy ranges and whether your daily function, energy, and fitness are where you want them to be. Weight is one data point, not the full picture.