Ideal Body Weight & Protein

Ideal body weight (IBW) is a reference weight derived from your height, originally developed for medication dosing rather than as an aesthetic goal. This tool shows four classic formulas — Devine (1974), Robinson (1983), Miller (1983), and Hamwi (1964) — each adding a fixed amount of weight per inch of height above five feet, with different coefficients for men and women. Seeing all four gives a range, not a single false-precision number.

Each was derived from different data and eras, so they use slightly different starting weights and per-inch increments — Hamwi and Devine run a little higher, Robinson and Miller a little lower. The spread between them is exactly the point: there is no single “ideal” weight, so the range across the four is a more honest answer than any one alone.

Not literally. IBW is a height-based reference that does not account for build, muscle mass, or composition — a muscular person can sit well above their IBW and be very healthy. Treat it as a rough anchor, not a target to hit exactly. A body-fat estimate and waist-to-height ratio describe health far better than a target weight.

Anchoring protein to IBW rather than actual weight keeps the target sensible regardless of current body fat: roughly 0.7g per pound of IBW for maintenance and about 1.0g per pound for active people or those over 40 (ISSN and ACSM guidance), plus a ~30g first-meal target from leucine-threshold research. The Macronutrient Calculator uses the same IBW-anchored approach.

IBW knows only your height and sex. It ignores frame size, muscle mass, and fat distribution — so it underestimates a healthy weight for muscular people and can flatter someone who has lost muscle. It was never intended as a health target; its enduring use is as a clinical anchor for dosing and protein targets. For health, composition and fat-distribution measures are more informative.