Healthy Weight Calculator with 5 Formulas

Calculate your healthy weight using Lorenz, Broca, Keys, Perrault formulas. Average of all formulas and BMI range.

How to Calculate Your Healthy Weight

Healthy weight is the body weight at which your body functions optimally, with the lowest risk of weight-related diseases. This calculator applies four scientific formulas and averages them, offering a more robust estimate than using a single formula.

The Formulas Used

Lorenz Formula — the most well-known, sex-specific:

Men: height - 100 - (height - 150) / 4
Women: height - 100 - (height - 150) / 2

Broca Formula — the simplest:

Men: height - 100 | Women: height - 104

Keys Formula — based on ideal BMI:

Men: height(m) squared x 22.1 | Women: height(m) squared x 20.6

Perrault Formula — accounts for age:

height - 100 + (age / 10) x 0.9

Which Value to Choose

The formula average is a good starting point, but the BMI normal weight range is the most authoritative reference according to WHO. If your current weight falls within that range and you feel well, you are likely at your healthy weight.

For a more complete assessment, the BMI calculation classifies your current situation, while body fat analysis reveals body composition beyond simple weight.

Frequently Asked Questions

Why do different formulas give different results?▼

Each formula was developed in different eras, with different populations and criteria. Broca's formula (1871) is the simplest and tends to overestimate for tall people. Lorenz (1929) is more refined. Keys uses a reference BMI. No formula is "correct" in absolute terms: the BMI range 18.5-24.9 remains the most reliable reference according to WHO.

Does healthy weight change with age?▼

Yes, healthy weight tends to increase slightly with age. Body composition naturally changes: you lose muscle mass (sarcopenia) and tend to accumulate more fat. Some studies suggest that in older adults, a BMI between 23 and 28 is associated with lower mortality compared to the classic 18.5-24.9 range.

What is the difference between healthy weight and ideal weight?▼

The terms are often used interchangeably, but technically healthy weight is the weight at which you feel well and your body functions optimally, while ideal weight is a mathematically calculated value. Two people of the same height may have different healthy weights based on body composition and overall health.