Ideal Weight Calculator

What this calculator does & how it works

This tool estimates a "healthy" body weight for your height and sex using four formulas that clinicians have used for decades. Rather than pretending there is one perfect number, it reports all four and presents the spread as a range, because your healthy weight is genuinely a band rather than a single point. Every formula here works the same way: it sets a base weight at five feet of height and adds a fixed amount for each inch above that.

The four methods are the classic ideal-body-weight formulas: the Devine formula (1974), originally created to guide medication dosing and still the most widely cited; the Robinson formula (1983) and the Miller formula (1983), which were refinements of Devine's work; and the Hamwi formula (1964), a fast clinical rule of thumb. Each uses a different base weight and per-inch increment for men and women, which is why the results differ by a few kilograms. If you enter imperial units, your height is converted to centimetres first and the final weights are converted back to pounds.

How to interpret your results

Read the range, not any single formula. If your weight already sits inside or near the band, that is reassuring. If it falls outside, that alone does not mean anything is wrong — these formulas ignore muscle, frame size, age, and body composition, so a strong, athletic build can legitimately exceed the range. The individual rows are shown mainly so you can see how much the methods disagree.

For a fuller picture, combine this with your BMI, which also factors in your actual weight, and your daily calorie needs if you are planning a change. No single tool defines a healthy weight; they are most useful together.

Limitations and when to consult a professional

These formulas are old and were derived from limited populations, mostly to standardise medication dosing rather than to define wellbeing. They depend only on height and sex, so they cannot account for body frame, muscularity, fat distribution, ethnicity, or age. They are not validated for children or adolescents, and they can mislead for very short or very tall people, pregnant people, and athletes. The "ideal" label is historical, not a judgement about your health.

If you are thinking about losing or gaining weight, have a condition that affects body composition, or feel anxious about your weight, talk to a doctor or a registered dietitian. They can interpret these numbers within your full health context and set a realistic, safe target — something a formula cannot do. Nothing here is medical advice.

Frequently asked questions