Historical ideal-weight formula comparison
These equations give different reference values from height and sex coefficients. The lowest and highest values are the span of four model outputs, not a healthy-weight interval or an individual goal.
For a separate adult BMI screening calculation based on actual height and weight, use the BMI Calculator .
The formula
The formulas follow Table 3 in Peterson et al. (2016), including that table’s Miller coefficient version. Hamwi is evaluated in pounds before conversion; the other equations start in kilograms. Height must be 60–98.4252 inches (152.4–250 cm), so the calculator does not extrapolate the per-inch-above-five-feet rule downward. All comparisons use unrounded values.
Four equations at five feet ten inches
For male coefficients and 177.8 cm (70 inches), x is 10. Devine gives 73 kg, Robinson 71 kg, Miller 70.3 kg, and Hamwi 166 lb = 75.2963 kg. The equation span is 70.3–75.2963 kg, with a spread of 4.9963 kg; it is not a recommended weight range.
How to use this calculator
- Select the published sex coefficients and enter an adult height of at least 152.4 cm or 60 inches.
- Choose the result weight unit and primary historical equation.
- Calculate, then open the equation table to compare all four model results.
An equation named ideal does not establish an ideal
The familiar term identifies a set of historical formulas. The result is driven by height and a sex-specific base value, without current weight, age, body composition, fitness, or medical context. The calculator does not decide whether you should gain or lose weight. Its purpose is to reproduce and compare the equations clearly when those names appear in a reference or another calculation.
Understand why the estimates disagree
Each formula starts with a different reference weight at five feet and adds a different amount for every additional inch. The gap between formulas can therefore change with height. Hamwi is originally expressed in pounds, while the others use kilograms. The calculator evaluates the original form before converting, rather than substituting rounded metric coefficients that can produce a slightly different result.
Interpret the span as a formula comparison
The lowest and highest outputs show which of the four equations returns the smallest and largest number for your inputs. They are not confidence limits, clinical cutoffs, or evidence of an appropriate personal interval. Miller coefficients can vary across published summaries; this page names the Table 3 version it implements. Heights below five feet are rejected to avoid an unstated downward extension, and the formulas are not intended as pediatric or pregnancy weight targets.
Assumptions & limitations
What this calculation assumes
- Uses the four equations as tabulated by Peterson et al., without frame-size adjustments.
What to keep in mind
- Supports adult heights from 152.4 to 250 cm only.
- Does not supply a healthy-weight interval, individual weight goal, diet, or medication dose.
- Published equation versions can differ; the implemented coefficients are shown explicitly.
Common questions
Is the lowest-to-highest span a healthy-weight range?
No. It is simply the minimum and maximum of the four formula results for the entered height.
Why does Hamwi differ from calculators using rounded kg coefficients?
This calculator evaluates the original pound equation and converts with exactly 0.45359237 kg/lb. Rounded metric shortcuts can differ.
Why is a height below five feet rejected?
These equations are stated as a base at five feet plus an increment above five feet. This implementation does not assume a downward extrapolation.