Ideal Weight Calculator – Devine, Robinson, Miller & Hamwi






Ideal Weight Calculator – Devine, Robinson, Miller & Hamwi

Ideal Weight Calculator

Calculate your ideal body weight using multiple scientifically-backed formulas.




Your Information
Gender

Frame Size

Unit

Height

ft

in

Current Weight (Optional)

lb




Your Ideal Weight
Recommended Ideal Weight

lb
Healthy range: — to — lb

Devine Formula
lb

Robinson Formula
lb

Miller Formula
lb

Hamwi Formula
lb

What is Ideal Body Weight?

Ideal body weight (IBW) is an estimated weight range associated with optimal health outcomes. Unlike BMI alone, IBW formulas specifically account for height and gender differences.

These formulas were originally developed for medical dosing calculations but have become popular tools for setting healthy weight goals.

IBW Formulas Explained

Formula Men (at 5’0″) Per Inch Over
Devine (1974) 110 lb + 5.1 lb
Robinson (1983) 114 lb + 4.2 lb
Miller (1983) 123 lb + 3.1 lb
Hamwi (1964) 106 lb + 6 lb

Women’s formulas start lower and add less weight per inch. We average all four formulas for a balanced estimate.

Frame Size Adjustments

  • Small frame: Subtract 10% from calculated ideal weight. Typically narrower shoulders and hips.
  • Medium frame: Use calculated ideal weight as-is. Average bone structure and proportions.
  • Large frame: Add 10% to calculated ideal weight. Broader shoulders, larger bone structure.
  • How to measure: Wrap thumb and middle finger around wrist. Overlapping = small; touching = medium; gap = large frame.

Important Considerations

  • Muscle mass: Athletes may have higher ideal weights due to muscle being denser than fat.
  • Age factor: These formulas don’t account for age-related changes in body composition.
  • Individual variation: Genetics, ethnicity, and health conditions affect optimal weight.
  • Not for children: Use age-specific growth charts for anyone under 18.