Health

Ideal Weight Calculator

Side-by-side estimates from Devine, Robinson, Miller and Hamwi formulas, plus a healthy BMI range. Free.

Metric (cm, kg) Imperial (ft/in, lb)

Gender

Male Female

Height (cm)

Average ideal weight

— kg

Enter height and gender to estimate

Devine (1974) —

Robinson (1983) —

Miller (1983) —

Hamwi (1964) —

Healthy BMI range —

What is "ideal weight"?

Ideal body weight (IBW) is a target weight estimated from height (and sometimes age and frame size). The concept dates to insurance industry tables from the early 20th century, which paired height ranges with weights associated with the lowest mortality. Modern medicine uses IBW formulas mainly for clinical purposes — drug dosing in obese patients, ventilator tidal-volume settings, and pediatric prescribing — not as a personal goal weight. Four formulas dominate: Devine (1974) and Robinson (1983) are linear with height above 5 ft, with Devine giving the most aggressive numbers; Miller (1983) tends to give the gentlest estimates; Hamwi (1964) sits in the middle. Because they were fit on different populations and intended for different uses, expect the four to disagree by 5-8 kg. A more meaningful range for general health is the BMI window of 18.5-24.9 kg/m², which usually spans about 15 kg at any given height. Use these numbers as a context, not a rule. Body composition, lifestyle, and your own history matter more than any single "ideal" digit.

How to use this calculator

1. Choose metric or imperial. 2. Pick your gender. 3. Enter your height. The calculator returns four estimates — Devine, Robinson, Miller, Hamwi — side by side, the average across the four, and the corresponding BMI 18.5-24.9 weight range. Compare the spread; if your real weight sits inside or near it, you're in the medical "healthy weight" zone.

The four formulas

All four formulas are anchored at 5 ft (60 in) and add a linear bonus per inch above. Letting over = inches over 60: Devine — Men: 50 + 2.3 × over | Women: 45.5 + 2.3 × over Robinson — Men: 52 + 1.9 × over | Women: 49 + 1.7 × over Miller — Men: 56.2 + 1.41 × over | Women: 53.1 + 1.36 × over Hamwi — Men: 48 + 2.7 × over | Women: 45.5 + 2.2 × over For sub-5 ft heights, Devine and Hamwi can return implausibly low numbers; Miller and Robinson are gentler in that range. The healthy BMI range is computed as 18.5·m² … 24.9·m² where m is height in meters.

Formula reference table

Each formula starts at 5 ft and adds kilograms per inch over.

Formula	Men (kg)	Women (kg)
Devine	50 + 2.3 × (in − 60)	45.5 + 2.3 × (in − 60)
Robinson	52 + 1.9 × (in − 60)	49 + 1.7 × (in − 60)
Miller	56.2 + 1.41 × (in − 60)	53.1 + 1.36 × (in − 60)
Hamwi	48 + 2.7 × (in − 60)	45.5 + 2.2 × (in − 60)

Frequently asked questions

Which formula is the most accurate?

There is no single "most accurate" formula because none describes a real biological target. Devine is the most widely used clinically; Robinson and Miller correct some of Devine's drift at extreme heights. The average of all four, or the BMI range, is usually the most informative number for a general user.

Why don't these formulas use my age or muscle mass?

They were designed as simple bedside rules, not personalized targets. Two people with identical height can have very different healthy weights depending on muscle mass, frame size, and history. For a deeper view, combine this with body fat % and waist circumference.

I'm shorter than 5 ft / 152 cm — why are my numbers low?

Devine and Hamwi were designed around adult heights ≥ 5 ft and extrapolate poorly below that. Miller and Robinson behave better in that range, but for short stature, BMI 18.5-24.9 is generally the more useful guide.

Should I aim for the lowest of the four numbers?

No — there's no health benefit to targeting the lowest. Pick a weight that supports your sleep, training, energy and bloodwork, and that you can sustain without disordered eating. Many healthy people sit above the lowest formula estimate.

How is this different from a BMI calculator?

BMI checks where your current weight sits on a height curve. Ideal-weight formulas predict a single target weight from height and sex. We show both side-by-side: the BMI range gives you a window, the formulas give you anchors inside it.

Are these formulas useful for athletes?

Mostly no. Athletes — especially in strength and contact sports — routinely sit well above formula "ideal weight" while still being lean and healthy. Body composition is the better lens; ignore the formula and look at fat percentage and performance markers.

Ideal Weight Calculator