How the ideal weight calculator works
"Ideal weight" has no single agreed formula, so this calculator shows four commonly referenced ones side by side, all based on height with a fixed offset per 2.54cm (1 inch) above 5 feet:
Devine (kg): Men 50 + 2.3×(in over 5ft) · Women 45.5 + 2.3×(in over 5ft)
Robinson (kg): Men 52 + 1.9×(in over 5ft) · Women 49 + 1.7×(in over 5ft)
Miller (kg): Men 56.2 + 1.41×(in over 5ft) · Women 53.1 + 1.36×(in over 5ft)
Hamwi (kg): Men 48 + 2.7×(in over 5ft) · Women 45.5 + 2.2×(in over 5ft)
Robinson (kg): Men 52 + 1.9×(in over 5ft) · Women 49 + 1.7×(in over 5ft)
Miller (kg): Men 56.2 + 1.41×(in over 5ft) · Women 53.1 + 1.36×(in over 5ft)
Hamwi (kg): Men 48 + 2.7×(in over 5ft) · Women 45.5 + 2.2×(in over 5ft)
Step-by-step guide
- Select your biological sex.
- Enter your height in centimetres.
- Compare the four formula estimates and the averaged figure.
Why these formulas exist
The Devine formula, for example, was originally created in 1974 to help estimate drug dosing, not as a fitness target — its widespread adoption as a general "ideal weight" reference is a case of a clinical tool being repurposed well beyond its original intent. Use these figures as a loose reference alongside other health markers, not a strict goal.
Frequently asked questions
None is definitively 'correct' — they were developed decades apart for different original purposes (several for medical dosing calculations, not fitness). Showing all four gives a realistic range rather than a false sense of precision from a single number.
Treat it as a rough reference point, not a target to hit precisely. Frame size, muscle mass, and individual health context all matter more than matching a formula-derived number exactly.
BMI gives a healthy range based on your actual height and weight together. These formulas instead estimate a single point weight from height alone, using older reference formulas — use our BMI Calculator for the range-based approach.