Ideal Weight Calculator
Find your ideal body weight using four established medical formulas — Hamwi, Devine, Robinson, and Miller — plus the BMI healthy weight range for your height.
The Four Ideal Weight Formulas
| Formula | Year | Men (base + per inch) | Women (base + per inch) |
|---|---|---|---|
| Hamwi | 1964 | 48.0 kg + 2.7 kg/inch | 45.5 kg + 2.2 kg/inch |
| Devine | 1974 | 50.0 kg + 2.3 kg/inch | 45.5 kg + 2.3 kg/inch |
| Robinson | 1983 | 52.0 kg + 1.9 kg/inch | 49.0 kg + 1.7 kg/inch |
| Miller | 1983 | 56.2 kg + 1.41 kg/inch | 53.1 kg + 1.36 kg/inch |
“Per inch” refers to inches above 5 feet (60 inches). Base weight applies at exactly 5 feet tall.
Frequently Asked Questions
What is ideal body weight?
Ideal Body Weight (IBW) is a target weight based on height and sex, originally developed for clinical drug dosing. The most common formulas (Hamwi, Devine, Robinson, Miller) were created between the 1960s and 1980s. These formulas produce a range of values — none is universally 'correct.' They should be understood as reference points rather than prescriptive targets, as they don't account for muscle mass, body composition, or individual health factors.
Which ideal weight formula is most accurate?
None of the four formulas (Hamwi, Devine, Robinson, Miller) is consistently more accurate than the others. They were all developed before modern body composition methods and are primarily used in clinical settings for drug dosing (particularly for medications with narrow therapeutic windows). For personal health goals, the BMI healthy weight range (18.5–24.9) or body fat percentage targets are more meaningful guides than IBW formulas.
Is ideal body weight the same as healthy weight?
Not exactly. IBW formulas give a single point estimate for a given height, while 'healthy weight' covers a range (BMI 18.5–24.9). A person can be healthy at weights above or below the IBW estimate. More importantly, IBW doesn't account for muscle mass — a muscular athlete may be above their IBW while having an excellent body composition. Use IBW as one data point among several, not an absolute target.
Can I be healthy above my ideal body weight?
Yes. Many people are in excellent health at weights above standard IBW estimates, particularly if they have higher muscle mass. Conversely, being at a 'normal' BMI or IBW doesn't guarantee good health if body fat distribution (visceral fat) is unfavourable. Metabolic health markers (blood pressure, blood glucose, cholesterol) are more direct indicators of health than weight alone.