What Is a Healthy Weight for Your Height?

"Healthy weight" isn't a single number — it's a range, and the right range for you depends on your height, sex, age, and body composition. The most commonly used definition comes from BMI: a healthy weight is any weight that places your Body Mass Index between 18.5 and 24.9. For a person who is 5'9", that's roughly 125–168 lbs. For someone who is 5'4", it's 108–145 lbs. But BMI-based healthy weight ranges are population averages, not individual prescriptions. They don't account for muscularity, bone density, age-related muscle loss, or fat distribution. That's why clinical research has produced several competing ideal weight formulas — each calibrated differently and producing meaningfully different results for some individuals. This calculator presents the four most clinically referenced healthy and ideal weight formulas side by side: the BMI range (18.5–24.9), the Hamwi formula (widely used in clinical nutrition), the Devine formula (originally developed for drug dosing), and the Robinson formula (a later refinement). Understanding how these formulas compare for your specific height and sex gives you a more complete picture than any single number — and helps you set a realistic, health-informed weight target rather than an arbitrary one from culture or comparison.