Calculate your ideal body weight using 4 evidence-based formulas (Devine, Robinson, Miller, Hamwi). Find the healthy weight range for your height and gender.
An ideal weight calculator estimates a healthy target body weight based on your height and gender using established medical formulas such as Devine, Robinson, Miller, and Hamwi. Because each formula produces a slightly different figure, the calculator shows a range rather than a single fixed number.
68.7 – 72 kg
Ideal Weight Range
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Ideal Body Weight
Ideal Body Weight (IBW) is an estimated weight range associated with good health outcomes for a given height and sex. Unlike BMI, IBW formulas estimate the weight at which the body functions optimally — and at which clinical data shows reduced chronic disease risk. These formulas are widely used in medicine to calculate drug dosages, ventilator settings, and nutritional requirements.
This calculator applies four evidence-based formulas: Devine (1974) — the most-cited in clinical practice; Robinson (1983) — used in North American nutrition protocols; Miller (1983) — tends to produce the lowest estimates; Hamwi (1964) — tends to produce the highest estimates.
The Four Formulas
Devine (1974) — 50 kg (male) or 45.5 kg (female) + 2.3 / 2.2 kg per inch above 5 feet. The global standard for drug dosing and mechanical ventilation calculations.
Robinson (1983) — 52 kg base for males, lower per-inch increment. Common in clinical nutrition. Miller (1983) — 56.2 kg base, smallest per-inch increment, lowest estimates. Hamwi (1964) — 48 kg base + 2.7 kg/inch, highest estimates among the four.
BMI vs IBW
The healthy BMI range (18.5–24.9) translates directly into a weight range for any given height. For a 175 cm male, this corresponds to approximately 57–76 kg. IBW formulas typically land within this range, though they may differ by several kilograms.
Key difference: IBW formulas were derived from actuarial and clinical data and consider sex explicitly. BMI is purely mathematical and does not account for sex. In clinical settings, IBW is preferred for drug dosing; BMI for population-level health screening.
Limitations
All four IBW formulas (Devine, Robinson, Miller, Hamwi) were developed decades ago, primarily using data from specific population samples, and none account for body composition — a muscular person and a person with higher body fat at the same height can have very different "ideal" weights despite the formulas giving one number.
These formulas are best used as a general reference range rather than a strict target. Frame size, muscle mass, age, and overall health markers (blood pressure, blood sugar, cholesterol) give a much more complete picture of whether a given weight is actually healthy for a specific individual.
Key Facts
Muscle mass
Athletes often exceed IBW while having low body fat — the formulas do not account for body composition.
Age
Older adults may have different optimal weights due to changes in muscle mass and bone density.
Height below 5 feet
All four formulas were validated for adults taller than 152.4 cm and may be unreliable for shorter individuals.
Individual variation
Health is influenced by genetics, lifestyle, and fitness level — not just weight.
10% tolerance
Most clinicians consider a weight within 10% of IBW to be clinically acceptable.
Use as a starting point
IBW is a statistical reference range — a starting point for conversation with a doctor, not a strict personal target.
No single formula is universally 'most accurate' — each was developed for a specific clinical context. The Devine formula is most widely used in medicine for drug dosing. For a general estimate, the average of all four formulas (shown as the Ideal Weight Range) is the most balanced approach.
Being above your ideal weight doesn't automatically mean poor health. Muscle mass, body frame, age, and ethnicity all affect optimal weight. Clinicians typically consider a weight within 10–20% of ideal as acceptable. Focus on body composition and health markers rather than achieving an exact number.
No — all four formulas (Devine, Robinson, Miller, Hamwi) were validated only for adults. For children and teenagers, use age- and gender-specific growth charts from your pediatrician or national health guidelines.
They overlap but are not identical. The healthy BMI range (18.5–24.9) gives a broader weight range based purely on height, while ideal weight formulas also factor in gender and were derived from clinical outcome data. Ideal weight formulas typically land within the BMI-healthy range but can differ by 2–5 kg.
Ideal body weight is used to calculate medication doses (particularly for drugs that don't distribute into fat tissue), to set ventilator tidal volumes in ICU patients, and to estimate nutritional requirements. Using actual body weight for these calculations in overweight patients can lead to overdosing.
None is definitively "most accurate" — they were developed using different population samples and methods. The Robinson and Miller formulas are generally considered more modern refinements of the older Devine formula, but all four are estimates. Looking at the range across all four formulas gives a more realistic picture than relying on a single number.
These formulas don't account for muscle mass or frame size. Athletic or larger-framed individuals often exceed the calculated "ideal" weight while still being at a healthy body composition. Use the result as a general reference range, not a strict target, especially if you have above-average muscle mass.