Ideal Body Weight Calculator (Devine Formula)
Written by Thierno Sadou Diallo, formula verified per our methodology • Last checked on 9/5/2026
The Devine formula calculates a reference weight as 50 kg (men) or 45.5 kg (women), plus 2.3 kg for every inch above 1.52 m (5 feet). For a 175 cm tall man, this reference weight is about 70.5 kg.
Explanation
**Worth knowing before using this result**: the Devine formula, published in 1974 by Dr. B. J. Devine, was never designed as a personal weight goal. It was developed to calculate a reference weight for dosing certain medications (notably gentamicin, an antibiotic whose dose must be adjusted to the patient's weight to avoid kidney or hearing toxicity from overdosing). It was later adopted, more broadly than its original use, in some nutrition and fitness contexts as a weight benchmark. The calculation itself is a simple linear relationship with height: a base weight (50 kg for men, 45.5 kg for women) plus 2.3 kg for every inch (2.54 cm) of height above 1.52 m (60 inches). It doesn't account for age, body frame, muscle mass, or individual build, and it's recognized as being fairly inaccurate for shorter people. A realistic healthy weight depends on far more factors than height alone — body composition, muscle mass, and overall health status matter more than a single number derived from a 50-year-old formula. For a more widely used medical reference indicator today, see our BMI calculator, itself to be interpreted with the same caution.
Example: a man, 175 cm tall
Inputs
Height: 175 cm. Sex: male.
Calculation
175 cm equals 175 ÷ 2.54 ≈ 68.9 inches. Weight = 50 + 2.3 × (68.9 − 60) = 50 + 2.3 × 8.9 ≈ 50 + 20.46 ≈ 70.46 kg.
Result
The Devine formula gives a reference weight of about 70.5 kg for this height.
Frequently asked questions
Does the Devine formula give my actual ideal weight?
No, that was never its intended purpose: it was designed for a specific medical use (drug dosing), not as a personal weight goal. A realistic healthy weight depends on many individual factors (muscle mass, body frame, age, health status) that a formula based only on height and sex can't capture.
Why does the formula use inches rather than centimeters?
Because it was published in the United States in 1974, where the inch is the common unit of measurement. This calculator automatically converts the height you enter from centimeters, so no manual conversion is needed.
Do other reference-weight formulas exist?
Yes, several similar formulas exist (Robinson, Miller, and Hamwi, among others), each with slightly different coefficients, developed at different times and in different contexts. They give close but not identical results, which shows clearly that none of them is an absolute truth — more like historical benchmarks to interpret with caution.