Ideal Weight Calculator
Compare four ideal body weight formulas side by side
Advanced options
These four formulas are population-average heuristics that routinely disagree by several kilograms for the same person. Read the spread as a range to be aware of, not a target to hit — and not individual medical advice.
| Formula | kg | lb |
|---|---|---|
| Devine (1974) Most referenced | 20.0 | 44.1 |
| Robinson (1983) | 20.0 | 44.1 |
| Miller (1983) | 20.0 | 44.1 |
| Hamwi (1964) | 20.0 | 44.1 |
0.0-0.0 kg
Healthy BMI weight range (18.5-24.9)
0.0-0.0 lb
Same range in pounds
Live Comparison
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Metric & Imperial
Enter height in cm or feet and inches, weight in kg or lb
Honest Caveats
Flags heights outside the range these formulas were ever validated for
Frequently asked questions
Which ideal weight formula is the most accurate?
None of them is "correct" — they are four population-average heuristics from different decades that routinely disagree by several kilograms for the same person. Devine (1974) is the most widely cited in clinical settings, but that's because it was designed for drug-dosing calculations, not as a wellness target.
Why do the four results differ so much?
Each formula was fitted to a different population sample and era. They agree roughly at average heights and diverge more the further you are from that average. Treat the spread across all four as your range, not any single number as your goal.
Do these formulas work for very short or very tall people?
No formula here has a sanctioned variant below 5 feet (60 inches) — the underlying linear fits were never validated at that range and extrapolate to unrealistic values. This tool flags that explicitly and floors the output rather than showing a nonsensical result. The same caution applies at unusually tall heights.
What does the frame size adjustment do?
It nudges each formula's result by +/-10% for a large or small frame. It is a soft, informal heuristic (there is no standardized frame-size measurement behind it), not a precision adjustment — use it as a rough sanity check, not a substitute for the underlying formula.