How to Calculate Ideal Body Weight: 5 Formulas Compared
Ideal body weight (IBW) formulas were originally developed in clinical settings to guide medication dosing and nutritional support. None of them perfectly capture every individual's "best" weight, but they provide useful starting benchmarks.
The Five Main Formulas
All assume height in inches (or cm) and use 5 feet (60 inches) as the baseline.
Devine Formula (1974) โ Most Widely Used
Men: IBW = 50 kg + 2.3 kg per inch over 5 feet Women: IBW = 45.5 kg + 2.3 kg per inch over 5 feet
Robinson Formula (1983)
Men: IBW = 52 kg + 1.9 kg per inch over 5 feet Women: IBW = 49 kg + 1.7 kg per inch over 5 feet
Miller Formula (1983)
Men: IBW = 56.2 kg + 1.41 kg per inch over 5 feet Women: IBW = 53.1 kg + 1.36 kg per inch over 5 feet
Hamwi Formula (1964)
Men: IBW = 48 kg + 2.7 kg per inch over 5 feet Women: IBW = 45.5 kg + 2.2 kg per inch over 5 feet
BMI-Based Ideal Weight
Target a BMI of 22 (midpoint of healthy range 18.5โ24.9): IBW = 22 ร height (m)ยฒ
Comparison Example: 5'10" (70 inches) Male
| Formula | IBW |
|---|---|
| Devine | 75.0 kg (165 lb) |
| Robinson | 75.0 kg (165 lb) |
| Miller | 69.9 kg (154 lb) |
| Hamwi | 75.1 kg (165 lb) |
| BMI=22 | 73.5 kg (162 lb) |
Important Limitations
These formulas don't account for muscle mass, bone density, age, or ethnicity. An athletic person with high LBM may be "overweight" by IBW formulas but perfectly healthy. Use IBW as a rough reference, not an absolute target.
Use our ideal body weight calculator to compare all formulas at once.