What next?
A target weight only helps if you know the daily numbers behind it.
How to use this calculator
- Pick your sex.
- Enter your height.
- Read your ideal weight across common formulas.
What your result means
The figure is a reference weight from classic clinical formulas (Devine and others), originally created for medicine dosing — not a personal target. It ignores build, muscle and frame size, so treat it as a rough midpoint of a healthy range, not a goal to hit exactly.
Why this one is different
Four rows, four answers: Devine leads, Robinson and Hamwi sit beside it, and a healthy BMI band for your height follows. They disagree by several kilograms, and the tool prints that disagreement rather than resolving it — the width of the spread is the useful output, which makes the honest answer a range and not a target.
What "ideal weight" actually means
There is no single correct weight for a given height — but several formulas estimate a reasonable target. The Devine, Robinson and Hamwi formulas all start from a base weight at five feet tall and add a fixed amount per inch above that. They were originally designed for medication dosing, so treat them as rough guides.
A more modern approach is the healthy BMI range: any weight that keeps your body mass index between 18.5 and 24.9 is generally considered healthy. This tool shows both so you can see a sensible band rather than one number.
Formula
The healthy BMI range multiplies 18.5 and 24.9 by your height in metres squared.
Frequently asked questions
Which formula is best?＋
None is definitive. The healthy BMI range is the most widely used today; the Devine and Robinson formulas are shown for comparison. Athletes with high muscle mass will read as "overweight" on all of them despite being healthy.
Does this apply to children?＋
No. These formulas and the standard BMI thresholds are for adults. Children and teenagers use age- and sex-specific percentile charts instead.
Where do these formulas come from?＋
Devine, Robinson, Miller and Hamwi were all developed for clinical purposes such as drug dosing, not as aesthetic or health targets. That is why they give a single number rather than a range.
Why do the four formulas disagree?＋
They were fitted to different populations and eras, so their height coefficients differ. The spread between them is a useful reminder that no single figure is the right weight.
Does frame size change the answer?＋
Some formulas add or subtract roughly 10 percent for small or large frames, usually judged from wrist circumference or elbow breadth. Treat that as widening the range, not moving the target.
Is a healthy BMI range more useful?＋
Often, yes. A BMI range gives a band of reasonable weights for your height rather than one number, which better reflects how much natural variation there is between people.
Example calculation
A man who is 180 cm (about 5 ft 11 in) tall, using the Devine formula:
Ideal weight = 50 kg + (2.3 × 10.87)
Ideal weight ≈ 75.0 kg (a woman: 45.5 + (2.3 × 10.87) ≈ 70.5 kg)
Formulae like Devine give a single figure, but a healthy weight is a range that also depends on build and body composition.
Related calculators
Assumptions & limitations
Every figure here comes from a simplified model. Keep these limits in mind when reading your result:
- “Ideal” ranges are population guides (healthy-BMI band and Devine/Robinson-style formulas), not personal targets.
- They ignore body composition, frame size and athletic build.
- A healthy weight for you is best confirmed with a clinician.