NumberTally Ideal Weight Calculator
Compare all four classic ideal-weight formulas — Devine, Robinson, Miller, and Hamwi — for your height and sex. Results in kilograms and pounds, with the average and the BMI healthy range for context.
Advanced options
Puts the formula average next to the WHO BMI 18.5–24.9 range for your height.
Where the four formulas came from
None of these started as diet advice. Devine’s 1974 formula was built for drug dosing — many medicines scale with lean body mass, and pharmacists needed a quick estimate from height. Robinson (1983), Miller (1983), and Hamwi (1964) each refined the idea from life-insurance and clinical data. They disagree on purpose: each fitted a different dataset, so the spread between them is honest information, not error.
The average of the four is the most defensible single number — it smooths out each formula’s quirks. But all four assume an average frame; very large or small frames shift the sensible target by a few percent either way.
Ideal weight vs. a healthy BMI range
The formulas give one number (or a tight cluster); the WHO’s BMI range gives a wide band — 18.5 to 24.9 times your height squared. The formula average usually lands inside the lower half of the BMI band. Think of it this way: the formulas answer “what’s typical for this height,” while the BMI band answers “what’s the full span associated with good outcomes.” The comparison box below shows both for your height.
Estimates only — not medical advice. Talk to a healthcare professional about your health.
Frequently Asked Questions
Which of the four formulas is the most accurate?
None is “true” — each was fitted to different data. The average of all four is the most robust single estimate because it cancels out each formula’s bias. The chart above shows the full spread so you can see the honest range.
Why do men and women get different results for the same height?
The formulas encode average body-composition differences: at the same height, men typically carry more lean mass, so every formula sets a higher base weight for men and a lower one for women.
What if I am shorter than 5 feet?
The formulas still compute — they extrapolate linearly below the 5-foot base — but they’re less validated there, since they were built from adult data clustered around average heights. Treat sub-5-foot results as rough guides.
Should I adjust for a large or small frame?
Yes, roughly ±10% is the traditional frame adjustment: use the upper end of the spread for a large frame and the lower end for a small one. Wrist circumference is the usual quick frame check.
Is ideal body weight the same as a healthy BMI range?
No. Ideal-weight formulas give a point estimate from height and sex; the BMI range (18.5–24.9) gives a band tied to population health outcomes. The formula average usually falls inside the band — the comparison above shows both for your height.