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Ideal weight for your height

There is no ideal weight, there are four formulas that give four different numbers. Here they are together, with the BMI range alongside, so the real spread is visible.

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Your figures

The formulas were derived separately, so this changes the answer.

Result

Average of the four formulas (kg) 70.0
What each formula says
Hamwi72Devine70Robinson69Miller69
HamwiDevineRobinsonMiller
Lowest (kg)
68.7
Highest (kg)
72.0
BMI range, lowest (kg)
56.7
BMI range, highest (kg)
76.3

The four formulas and the BMI range

The four formulas and the BMI range
FormulaWeight
Hamwi formula (1964) 72.0
Devine formula (1974) 70.5
Robinson formula (1983) 68.9
Miller formula (1983) 68.7
Range from BMI 18.5-24.9 66.5

What we assume

  • All four formulas start at 5 feet (152.4 cm) and add a fixed amount per extra inch.
  • The BMI range uses 18.5 to 24.9 applied to your height.
  • No formula accounts for frame size, age or muscle mass.
  • These are population statistics for adults, not personal targets.

How it is calculated

All four formulas share a shape: a base weight at five feet, plus a fixed amount for every inch above that.

weight = base + increment × (inches − 60)

What each one says

Hamwi (1964) starts at 48 kg for men and 45.5 for women, adding 2.7 and 2.2 kg per inch. It was written to work out drug doses, not weight targets.

Devine (1974) is the most used: bases of 50 and 45.5 kg, and 2.3 kg per inch for both. It is still the hospital standard for adjusting medication.

Robinson (1983) and Miller (1983) revised Devine against real population data. Robinson lowers the increments; Miller raises the bases and lowers the increments further, so it reads highest for short people and lowest for tall ones.

Why we show all of them

Because they disagree, and the disagreement is the information. At 1.75 m the four answers spread across three kilos and a bit. If there were one exact ideal weight, they would agree.

In fact three of the four were designed to calculate drug dosages, not to tell anyone what to weigh. They drifted into popular culture along the way.

The BMI range

It is the most honest of the five numbers, because it is not a number: it is an interval. Solve for weight at BMI 18.5 and at 24.9 for your height, and everything in between counts as normal weight.

An example

For a man of 1.75 m: Hamwi gives 72.0 kg, Devine 70.5, Robinson 68.9 and Miller 68.7. A spread of 3.3 kg between the highest and the lowest, averaging 70.0. The BMI range runs from 56.7 to 76.3 kg, and all four sit comfortably inside it.

Frequently asked questions

Which of the four formulas is the right one?

None of them is "the right one". Devine is the most widespread and the one used for hospital dosing, but that makes it standard, not accurate. If you want a practical reference, the BMI range is more useful than any of them because it admits there is a margin.

Why do they not ask for my current weight?

Because these formulas do not use it: they depend only on height and sex. That is both their simplicity and their limit, since two people of the same height with very different builds get the same figure.

Do they account for frame size or age?

No. Hamwi described frame-size adjustments of about 10% that almost nobody applies, and none of them considers age. People lose muscle and gain fat at the same weight as they get older, and none of the four can see that.

Do they work for athletes?

Badly, for the same reason BMI does: they cannot tell muscle from fat. Someone carrying a lot of muscle will read above all four figures without that meaning anything is wrong.

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Updated on 2026-09-10. Calculations run in your browser; nothing you type is sent to a server.

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