What Is Ideal Body Weight?
Ideal body weight (IBW) is an estimate of the weight at which a person of a given height is likely to be healthiest and have the lowest risk of weight-related disease. Unlike BMI, which gives a broad range, IBW formulas produce a single target number — useful for clinical applications such as calculating medication dosages and nutritional needs.
The Four Main IBW Formulas
This calculator uses four established formulas and averages their results. The Hamwi formula (1964) is widely used in clinical dietetics. The Devine formula (1974) was originally developed for drug dosing. The Robinson formula (1983) and Miller formula (1983) were derived from actuarial data. Each formula gives a slightly different result — averaging them provides the most balanced estimate.
How to Use Your Ideal Weight
Your ideal weight is a target range, not a strict number. Aim to stay within 10% above or below the calculated average. Combining IBW with BMI and waist circumference gives a more complete picture of whether your current weight poses any health risks.