Ideal Weight Calculator
Estimate an ideal body weight range based on height, using the Devine formula.
How it works
This calculator estimates a reference "ideal" body weight using the Devine formula, which starts from a base weight at 5 feet tall and adds a fixed amount for every inch above that: 50 kg + 2.3 kg per inch over 5 feet for men, and 45.5 kg + 2.3 kg per inch over 5 feet for women.
For example, a man who is 5'10" (10 inches over 5 feet) has an estimated ideal weight of 50 + (2.3 × 10) = 73 kg. The formula is linear, so every additional inch of height adds the same fixed 2.3 kg to the estimate.
The Devine formula has an unusual origin: it was created in 1974 not as a fitness or wellness benchmark, but to help clinicians calculate accurate medication dosing, since some drug dosages are based on body weight and using someone's actual weight (rather than lean weight) can be inaccurate for people who are significantly over or under a "typical" build.
It's one of several similar height-based formulas developed for related purposes — the Robinson formula (1983), Miller formula (1983), and Hamwi formula (1964) all use a similar "base weight plus increment per inch" structure with slightly different constants, and none of them was designed as a personal fitness target.
Because it's based purely on height, this formula doesn't account for frame size, muscle mass, or body composition — a muscular, athletic person and a smaller-framed person of the same height get the identical "ideal weight" estimate, despite potentially very different healthy weights for their individual builds.
For these reasons, the result is best read as a general reference point or the center of a healthy range, rather than a strict number to hit — actual healthy weight varies meaningfully by individual factors this formula was never designed to capture.
Some other body-composition methods try to account for individual differences that height-only formulas miss — wrist circumference, for instance, is sometimes used as a rough proxy for frame size (small, medium, or large), on the idea that a larger-framed person naturally carries more healthy weight at the same height. This calculator doesn't incorporate frame size, which is part of why its result should be treated as a starting reference rather than a precise individual target.
Is this a strict target?
No — it's a general reference point; healthy weight varies by build, muscle mass, and other factors.
What is frame size, and does this calculator account for it?
Frame size (often estimated from wrist circumference) reflects bone structure differences between individuals — this calculator doesn't factor it in, which is one more reason to treat its result as a general reference rather than a precise target.
What is the Devine formula, and why was it created?
A 1974 formula originally developed to help estimate weight for medication dosing calculations in clinical settings — not to serve as a fitness or wellness target, though it's since become popular for that purpose too.
Are there other similar ideal weight formulas?
Yes — the Robinson, Miller, and Hamwi formulas use a similar height-based structure with slightly different constants, and all produce broadly similar (though not identical) estimates.
Does this formula account for muscle mass or body frame?
No — it's based purely on height, so it doesn't distinguish between someone with a muscular build and someone with a smaller frame at the same height.
Why do men and women get different formulas?
The formulas reflect average differences in body composition between men and women, using a lower base weight and the same per-inch increment for women.
Should I aim to weigh exactly this number?
Not necessarily — treat it as the center of a reasonable range rather than a precise target, since individual healthy weight depends on factors like muscle mass and frame size that this formula doesn't measure.
How much does each additional inch of height change the estimate?
2.3 kg (about 5 lb) per inch above 5 feet, for both the men's and women's versions of the formula.
Is this the same as a healthy BMI weight range?
It's related but calculated differently — BMI-based healthy weight ranges come from BMI category thresholds, while the Devine formula uses its own independent height-based formula. The two often overlap but won't produce identical numbers.
Why might my doctor use a different ideal weight calculation?
Clinicians may use whichever formula (Devine, Robinson, Hamwi, or others) is standard for their specific purpose, such as medication dosing — the differences between formulas are usually small but not zero.