Healthy Weight Calculator
Healthy weight range: 0
How This Range Is Calculated
The healthy weight range shown above uses the standard Body Mass Index formula — weight in kilograms divided by height in meters squared (BMI = kg / m²) — and finds the two weights that put you at the low and high edges of the widely-used "normal" BMI category, 18.5 to 24.9. That's the same classification system used by the BMI calculator, so if you already know your BMI, this just works the range backwards to a weight in pounds. We also show the Devine formula estimate (a reference point long used in clinical dosing calculations: 50 kg + 2.3 kg per inch over 5 feet for men, 45.5 kg + 2.3 kg per inch over 5 feet for women) purely as a second data point, not because it's more "correct" than the BMI range.
A Range, Not a Target
BMI doesn't distinguish muscle from fat, so a muscular, athletic person can land above this range while carrying a healthy amount of body fat, and a sedentary person can fall inside it while still carrying excess visceral fat. If you want a more direct read on composition, the body fat calculator and the ideal weight calculator (which compares several classic formulas side by side) fill in that gap. Treat the numbers here as an educational estimate, not medical advice — a doctor or registered dietitian can account for your frame, muscle mass, and health history in a way no formula can.
Frequently Asked Questions
How is the healthy weight range calculated?
It uses the standard BMI formula (weight in kg divided by height in meters squared) solved backwards for weight at the low and high edges of the widely-used normal BMI band, 18.5 to 24.9. Your height is converted from feet/inches to meters, then multiplied by 18.5 and 24.9 to get the two boundary weights, which are converted back to pounds.
Why does the calculator also show a Devine formula weight?
The Devine formula (50 kg + 2.3 kg per inch over 5 feet for men, 45.5 kg + 2.3 kg per inch over 5 feet for women) is a long-standing reference estimate originally developed for medical dosing calculations. It's shown alongside the BMI range as a second data point, not because it overrides the BMI-based range -- the two methods measure different things and can reasonably disagree.