How to Calculate Ideal Weight: Healthy Range and the Broca Formula
Ideal weight can be derived from the normal BMI range, or estimated from height with the Broca formula. Here is how the two compare.
The more robust approach works backwards from the normal BMI range: for a given height, compute the weight limits that keep BMI inside the normal band — that is the healthy weight range.
The (modified) Broca formula gives a quick single estimate: men ≈ (height cm − 100) × 0.9, women ≈ (height cm − 100) × 0.85. Sources vary slightly.
The healthy range gives you an interval while Broca gives a single point; as long as they point in the same direction, there is no need for them to match exactly.
Enter your height and weight in this calculator to get the BMI category, the healthy weight range, and (once you pick a sex) the Broca reference weight.