About the Ideal Weight
There is no single "ideal" weight, which is why this calculator shows four established formulas side by side plus the healthy BMI range for your height. Seeing the spread between them is the point: the answer is a range, not a target number.
How to use the Ideal Weight
- Enter your height and select your sex.
- Compare the results from the Devine, Robinson, Miller, and Hamwi formulas.
- Look at the healthy BMI range, which is usually the widest and most forgiving.
- Treat the overlap between methods as a sensible range rather than one exact figure.
Frequently asked questions
Why do the formulas disagree?
They were derived from different populations for different purposes — several originated in drug dosing rather than health guidance. A ten-kilogram spread between methods is normal and tells you the concept is inherently approximate.
Which method is most trusted?
The healthy BMI range is the one most widely used in modern clinical practice, because it gives a range rather than pretending to a single correct weight.
Does frame size change the answer?
Yes, meaningfully. Someone with a broad frame carries more healthy weight than someone slight of the same height, and none of these formulas measure that.
Is a lower weight always healthier?
No. Being underweight carries its own risks, including reduced bone density and impaired immune function. Health outcomes are best across a band, not at the bottom of it.
Ideal weight formulas are rough statistical guides that ignore muscle mass, frame size, age, and medical history. They are not a substitute for advice from a qualified health professional.