Overview
Ideal-weight formulas give a reference point for a healthy bodyweight based on height and sex. They predate modern body-composition tools, so treat the number as a guide rather than a target written in stone.
How it's calculated
Enter your height and sex. We compute the Devine estimate (the clinical standard, also used for drug dosing), the slightly different Robinson estimate, and the WHO healthy-weight range derived from a BMI of 18.5–24.9.
Devine (male): 50 + 2.3 × (height_in − 60) Devine (female): 45.5 + 2.3 × (height_in − 60) Robinson (male): 52 + 1.9 × (height_in − 60)
How to read your result
Use the BMI range as your healthy band and the Devine/Robinson numbers as a midpoint reference. Muscular people will sit above these estimates without being overweight — pair them with body-fat percentage for a fuller picture.
Frequently asked questions
Which formula is best?
Devine is the most widely used and is the clinical default. Robinson is a refinement; both land close together. The BMI range is the most evidence-based way to define 'healthy'.
Is there one perfect weight?
No — a healthy weight is a range, not a single number. These formulas give a midpoint; the BMI band shows the full healthy span for your height.
Do these work for athletes?
Less well. Muscle adds weight without adding fat, so trained lifters often exceed 'ideal' figures while being lean. Use body-fat percentage alongside them.
Sources & references
- Devine BJ. Gentamicin therapy (ideal body weight formula). Drug Intell Clin Pharm. 1974;8:650-655.
- Robinson JD, et al. Determination of ideal body weight for drug dosage calculations. Am J Hosp Pharm. 1983;40(6):1016-1019.
Medical disclaimer
This calculator is for general educational purposes only and is not medical advice. Estimates are based on population formulas and may not fit your individual situation. Consult a qualified healthcare or fitness professional before making health, nutrition or training decisions.