Ideal Weight Calculator — Devine, Robinson, Miller & Hamwi

Metric (cm) Imperial (ft / in)

Height (cm)

Sex

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About the Ideal Weight Calculator

This calculator estimates a healthy target weight for your height using four of the most widely cited ideal-body-weight (IBW) formulas, then compares them against the weight range that keeps your Body Mass Index in the healthy 18.5–24.9 band. Because each formula was built from a different study population, they rarely agree exactly — seeing all four at once (plus the BMI range) gives you a sensible band to aim for rather than a single, falsely precise number.

Devine (1974): the clinical standard, still used for drug dosing. Male 50 kg, female 45.5 kg base, +2.3 kg per inch over 5 ft.

Robinson (1983): a refinement of Devine that tends to give slightly lower figures.

Miller (1983): uses a smaller per-inch increment, so tall people get lower estimates.

Hamwi (1964): the original quick bedside method, generally the highest of the four for taller heights.

These formulas depend only on height and sex — they ignore age, frame size, muscle mass and body composition. They're a helpful reference point, not medical advice. For personal targets, talk to a qualified healthcare professional.

How it works

Three steps. No sign-up, no upload, no wait.

Choose your units

Pick metric (cm) or imperial (feet & inches), then enter your height.

Select your sex

The classic formulas use different constants for males and females.

Read your results

See the ideal weight from four well-known formulas plus your healthy BMI weight range.

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Private by design.Everything happens right here in your browser. Your files are never uploaded — we never see them.

Frequently Asked Questions

What is “ideal body weight” and how is it calculated? ▼

Ideal body weight (IBW) is an estimate of a healthy weight for a given height, originally created to help doctors dose medication. This tool shows four classic formulas — Devine, Robinson, Miller and Hamwi. Each starts from a base weight at 5 feet (60 inches) of height and adds a fixed amount of weight for every inch above that, with different constants for males and females.

Which formula should I use? ▼

There's no single “correct” one — they were derived from different populations and give slightly different numbers. The Devine formula (1974) is the most widely used in clinical settings. It's often most useful to look at the whole range the four formulas produce rather than any single figure, and to compare it against the healthy BMI weight range.

How is the healthy BMI weight range worked out? ▼

A Body Mass Index between 18.5 and 24.9 is generally considered healthy for adults. We rearrange the BMI formula (weight = BMI × height²) to find the lowest and highest weights that land in that band for your height, so you get a realistic range rather than a single target.

Do these formulas account for age, build or muscle? ▼

No. They depend only on height and sex. They don't consider frame size, muscle mass, body-fat percentage, age or ethnicity, so a very muscular or large-framed person may sit above the “ideal” figure while still being healthy. Treat the results as a rough guide, not a medical verdict.

Are these numbers suitable for children? ▼

No. These formulas were designed for adults. Healthy weight for children and teenagers is assessed with age-and-sex-specific growth charts and BMI percentiles, so please don't apply this tool to anyone under 18.

Is my height data sent anywhere? ▼

No. Every calculation runs entirely in your browser using plain JavaScript. Your height, sex and results never leave your device and nothing is uploaded.