Ideal Weight Calculator

“Ideal weight” is the historical name of these height/sex equations. The outputs are reference values, not measurements of body composition or a weight proven to maximize an individual’s health.

The form compares variants named Robinson, Miller, Devine, Hamwi and modified Broca. Miller, Devine, Hamwi and Broca retain the site’s existing coefficients; their original full publications and dates were not independently verified here. Their arithmetic mean summarizes the displayed equations; averaging does not validate a personal target.

Robinson et al. (1983) derived regressions from Metropolitan Life Insurance Company height/weight tables for drug-dosage calculations. The original all-frame coefficients were 51.65 + 1.85 per inch for men and 48.67 + 1.65 for women above 60 inches. This calculator retains the rounded 52/1.9 and 49/1.7 comparison variants rather than claiming an exact reproduction. Source checked 30 September 2026.

At 177.8 cm (70 inches), the male Devine variant gives 50 + 2.3 × (70 − 60) = 73.0 kg. This example demonstrates arithmetic, not a recommended weight.

Several formulas have been developed to estimate ideal weight. Each applies different assumptions and was derived from different populations:

1. Robinson Formula (1983)

This is the rounded comparison variant described above; its label does not establish individual accuracy.

2. Miller Formula — site comparison variant

The retained Miller coefficients differ from the other site variants. Naming the comparison does not establish original-source equivalence or individual accuracy.

3. Devine Formula — site comparison variant

This retained site variant uses the displayed coefficients. The original publication and its individual validation domain were not independently verified for this review.

4. Hamwi Formula — site comparison variant

The retained site coefficients increase the reference mass for each inch of height above 60. They are displayed for comparison, without a claim of verified original-source equivalence.

5. Broca Index — modified site comparison variant

This site variant subtracts 100 cm from height and applies a further 15% reduction for the female coefficient option. It is explicitly a retained comparison rule, not a verified original clinical prescription.

The historical Robinson paper fitted separate frame-specific regressions. A universal 10% adjustment to every equation is not established by that source, and a selector that changes only a label does not adjust the calculation.

This form therefore uses no frame selector or frame multiplier. Wrist circumference alone is not used to personalize these reference values. The section remains available to explain the limits of the earlier frame-size claim.

Height/sex inputs omit age, muscle mass, bone structure, pregnancy, illness, and individual history. A positive, finite output establishes arithmetic feasibility, not clinical suitability.

The form refuses nonpositive reference masses or nonfinite results instead of displaying impossible values. It does not substitute a new population model or silently clip an equation.

The displayed BMI-derived weight interval is 18.5 × height² to 24.9 × height². CDC adult BMI guidance applies its adult categories to people aged 20 or older and calls BMI a screening measure, not a diagnosis. This height-only form cannot confirm age or suitability. Source checked 30 September 2026.

A useful health assessment considers measurements, medical history, activity, physical examination and, when relevant, laboratory findings. A historical reference equation cannot choose a diet, exercise prescription or treatment.

If you compare measurements over time, retain the same units and method. Changing an input clears the result so that an earlier calculation is not attached to new measurements.

Why do the equations disagree?

They have different coefficients and reference assumptions. The five results and their mean show that disagreement directly; no result is selected as the most accurate.

Does a lower or higher weight mean poor health?

The equations do not classify your current weight, fat mass or health. Their average and the BMI-derived interval are descriptive reference calculations.

Can these be used for children, pregnancy or athletes?

This form has no model for those situations. It does not establish that an adult height/sex reference equation applies to them.