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Ideal Weight Range Calculator

Estimate a healthy or ideal weight range from your height, sex, age and body-frame context. Compare BMI-based ranges with common ideal body weight formulas including Devine, Robinson, Miller and Hamwi.

Calculator

Used for all ideal weight formulas.

cm

Used by several ideal body weight formulas.

Adult ranges are most meaningful for 18+.

years

Adjusts the practical range slightly.

Used to compare against the range.

kg

Custom BMI range

Adjust the BMI range used for the healthy weight calculation.

BMI healthy range
Formula average
Frame-adjusted range
Height used

Formula comparison

MethodEstimateNotes

Personalised interpretation

How the calculation works

The calculator shows two main types of estimate. The BMI range calculates the weight range that corresponds to your selected BMI limits. The formula estimates use common ideal body weight equations based mainly on height and sex.

BMI weight = BMI × height²

Devine, Robinson, Miller and Hamwi formulas were originally designed as simple ideal body weight estimates. They do not directly measure body fat, muscle mass or health.

The frame-size option widens or shifts the practical range slightly. A small frame may sit nearer the lower part of the range, while a larger or more muscular build may sit nearer the upper part.

Note: This calculator is for general guidance only. Ideal weight is not a diagnosis. Health also depends on waist size, blood pressure, fitness, strength, blood markers, age, medical history and body composition.

When ideal weight formulas can be misleading

High muscle mass

Muscular people can weigh more than formula estimates while still being healthy and lean.

Older adults

Strength, appetite, frailty risk and unplanned weight loss may matter more than aiming for a low formula weight.

Children and teenagers

Adult ideal weight formulas are not appropriate for children, who need age- and sex-specific growth charts.

Pregnancy

Pregnancy changes weight needs and should be assessed using pregnancy-specific guidance.

Common questions

What is the best ideal weight formula?
There is no single best formula for everyone. BMI ranges are useful for general screening, while formulas such as Devine, Robinson, Miller and Hamwi are simple estimates based on height and sex.
Is ideal weight the same as healthy weight?
Not exactly. Healthy weight is usually a range, not one number. A single ideal number can ignore body frame, muscle mass and personal health context.
Why does body frame matter?
People with the same height can have different bone structure and muscle mass. A larger frame often sits naturally higher in the range, while a smaller frame may sit lower.
Should I aim for the midpoint?
Not necessarily. The midpoint is only a reference. For many people, a sustainable weight near the upper or lower part of the range may be more realistic and healthier.

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