Ideal Weight Calculator

What is your ideal weight? It is a common question with a surprisingly nuanced answer — one that depends not just on your height and gender, but on which medical formula you use and your personal health goals. Our free Ideal Weight Calculator applies four established medical formulas — Robinson (1983), Miller (1983), Devine (1974), and Hamwi (1964) — to provide a range of ideal body weight estimates based on your height and gender. Rather than giving a single potentially misleading number, the calculator presents all four formula results side by side and computes a healthy weight range that spans from 85% to 115% of the average, giving you a realistic target window that accommodates different body types, muscle mass variations, and personal preferences. These formulas are standard tools used by medical professionals for dosing medications, assessing nutritional status, setting health benchmarks, and calculating appropriate body weight for clinical procedures. The Devine formula, first published in 1974, was originally developed to calculate drug dosages and remains widely used in clinical settings today. The Robinson and Miller formulas (both 1983) updated the Devine equation using more recent population data from life insurance actuarial tables. The Hamwi formula (1964) was developed for calculating ideal body weight in the context of diabetes management and nutritional planning. By averaging four independent formulas, the calculator produces a robust estimate that is less sensitive to the quirks of any single equation, giving you a well-rounded picture of what a healthy weight target might look like for your height and gender.

Understanding Ideal Weight Formulas

Each formula calculates ideal weight differently because they were developed using different population data sets and for different clinical purposes. The formulas all start from a base weight at a reference height of 5 feet (152.4 cm) and add an incremental amount for each inch of height above that baseline. For men, the base weights range from 48 kg (Hamwi) to 56.2 kg (Miller), and the per-inch increments range from 1.41 kg (Miller) to 2.7 kg (Hamwi). For women, base weights range from 45.5 kg (Devine and Hamwi) to 53.1 kg (Miller), with per-inch increments ranging from 1.36 kg (Miller) to 2.3 kg (Devine). These variations reflect the different populations studied and the mathematical approaches chosen by each researcher. Modern clinical practice generally considers a healthy weight range rather than a single ideal number, which is why our calculator presents a range spanning ±15% around the average of all four formulas. This range approach acknowledges that healthy body weight depends on additional factors including frame size, muscle mass, bone density, and body composition — all of which vary naturally between individuals of the same height and gender. For the most personalized assessment, combine the ideal weight range from this calculator with other health metrics such as body fat percentage, waist-to-hip ratio, blood pressure, and lipid profile, and discuss your health goals with a qualified healthcare provider.