Ideal Weight Calculator (Devine, Robinson, Miller, Hamwi)
Estimate ideal body weight from height and sex using four classic clinical formulas, plus the healthy BMI weight range. Free, in your browser.
Healthy BMI range: 56.7 kg – 76.3 kg
🔒 Calculated in your browser. Four classic clinical formulas plus the healthy-BMI weight range — estimates for a frame, not a target; healthy weight is a range, not one number.
Four formulas plus a BMI range
Enter your height and sex to see ideal-body-weight estimates from the Devine, Robinson, Miller and Hamwi formulas — the classic equations used in clinical dosing and fitness. Alongside them, the tool shows the healthy weight range for your height at BMI 18.5–24.9.
A range, not a target
These formulas were built for medication dosing and give a single figure per height, but real healthy weight is a range that depends on build, muscle and body composition. Treat the numbers as a rough reference, not a goal. Everything is calculated in your browser.
These four formulas were not written for you
Devine, Robinson, Miller and Hamwi all come from clinical practice, and Devine's — the oldest and still the most cited — was published in 1974 to size drug doses, not to tell anyone what to weigh. Each is the same shape: a base weight at five feet, plus a fixed amount for every inch above that. They contain no term for your build, your muscle, your age or your health. Two people of the same height get the same answer whatever else is true of them.
The BMI range is the more honest number
Alongside the four is the weight range that puts you between BMI 18.5 and 24.9 at your height — a band rather than a point, and the one clinicians actually use when they mean healthy weight. Expect the four formulas to land near its lower half. Below five feet the formulas are not extended downwards, because a straight line continued past the data it was fitted to starts returning weights that no source supports; the page shows the base weight and says so.
Frequently asked questions
What is ideal body weight?
A formula-based estimate of a "reference" weight for a given height and sex, originally for medication dosing. It ignores build and muscle, so use the BMI range too.
Which formula should I use?
They give slightly different numbers; Devine is the most widely cited. Seeing all four plus the BMI range gives a realistic range rather than one figure.
Which of the four numbers should I use?
None of them, as a target. They exist so that two clinicians sizing the same dose get the same answer. If you want a figure to aim at, the BMI range is the defensible one, and it is a range on purpose.
Why is my height under five feet treated differently?
All four formulas are defined as a base weight plus so much per inch over five feet. Below that there is no agreed way to continue them, so the page returns the base weight and marks it rather than inventing a downward slope.
Does it account for muscle?
No, and neither does BMI. A heavily muscled person will read as overweight on both. That is a known limit of every height-only measure, not a fault in the arithmetic.