What is ideal body weight?
Ideal body weight (IBW) is an estimate of the weight that is associated with the lowest risk of health problems for a person of a given height. Several formulas have been developed over the years to calculate IBW, each with slightly different results. Our calculator lets you compare four of the most widely used formulas side by side.
The four formulas explained
- Devine (1974): The most commonly used formula, originally developed for drug dosing calculations.
- Robinson (1983): A refinement of the Devine formula with slightly lower estimates for taller individuals.
- Miller (1983): Another variation that tends to give higher ideal weights.
- Hamwi (1964): One of the oldest formulas, still used in some clinical settings.
Ideal weight vs healthy BMI range
While IBW formulas give a single target number, the healthy BMI range (18.5-24.9) provides a broader weight range that is considered healthy for your height. Both approaches are useful — IBW gives you a specific goal, while the BMI range gives you flexibility.