Find your ideal body weight using 4 proven medical formulas. See your healthy weight range and exactly how much to gain or lose.
An Ideal Weight Calculator helps you determine the optimal body weight for your height and gender using scientifically validated formulas. It is used by doctors, dietitians and nutritionists as a starting point for weight management guidance. This calculator compares four established medical formulas simultaneously to give you the most comprehensive result.
The concept of "ideal body weight" was originally developed for medical dosing calculations, particularly for medications where dosage depends on lean body mass. Over time, these formulas became widely used in nutrition and fitness contexts. While no single number defines the perfect weight for every individual, the average of multiple formulas provides a reliable and evidence-based target range.
| Height | Male IBW (Avg) | Female IBW (Avg) | BMI at IBW |
|---|---|---|---|
| 155 cm | 56 kg | 52 kg | ~22 |
| 165 cm | 63 kg | 58 kg | ~22 |
| 175 cm | 70 kg | 64 kg | ~22 |
| 185 cm | 78 kg | 72 kg | ~22 |
Ideal weight calculators like the Ponderal Index (PI = weight/height³) target a PI of 11–14 kg/m³ for normal weight. The IBW formulas above typically produce weights corresponding to BMI 20–25, which aligns with low health risk according to WHO guidelines.
Enter your height, current weight and gender. Click Calculate to see all four formula results, the average ideal weight, healthy range (±10%) and how much you need to gain or lose to reach your ideal weight.
These formulas do not account for muscle mass, body frame size, age or ethnicity. Athletes and bodybuilders will weigh more than the IBW without excess fat. Elderly individuals may have different optimal weights. Always consult a healthcare professional before beginning any weight loss or gain program.
The four formulas (Hamwi, Devine, Robinson, Miller) were developed between 1964 and 1983 and remain the most widely cited IBW equations in medical literature. The average of all four is considered more reliable than any single formula. A ±10% range around the average defines the "healthy weight zone" used in clinical practice.