How to use the ideal weight calculator
- Pick your sex and enter your height.
- The healthy BMI range is shown first — that's the most widely used guide.
- The table compares four classic formulas so you can see the spread between them.
Why the formulas disagree
Devine (1974) was originally created for calculating medication doses, not health targets, and Robinson, Miller and Hamwi are variations built on the same idea: a base weight at 5 feet, plus a fixed amount per additional inch. Because they use height alone, they can't distinguish a muscular athlete from someone carrying more fat, and they typically produce a single number rather than a range. That's why the BMI range (18.5–24.9) is the more useful everyday guide — and even that is a population-level tool, not a personal verdict.
Benefits
- Shows the healthy BMI-based weight range for your height.
- Compares four classic clinical formulas (Devine, Robinson, Miller, Hamwi).
- Metric and imperial units.
- Honest about how much the formulas disagree and why.
Limitations to know
- The formulas use height and sex only — they ignore muscle, frame and body composition.
- They date from the 1960s–80s and were not designed as personal health targets.
- A single "ideal" number is less meaningful than a healthy range.
Common mistakes to avoid
- Treating one formula's number as a definitive goal weight.
- Applying it to athletes, where extra muscle skews the result.
- Using it instead of, rather than alongside, professional advice.
Alternatives
For your current category use the BMI Calculator; for composition use the Body Fat Calculator.
Last updated: August 2026 · Reviewed by the AI Toolbox editorial team.
Frequently asked questions
Which number should I use?
The BMI-based range is the most practical. The formulas are shown for comparison and historical context.
Why is there no age input?
These formulas depend only on height and sex. Age affects body composition but isn't part of them.
Does it work for athletes?
Poorly — muscle weighs more than fat, so muscular people often exceed these figures while being perfectly healthy.
Is this medical advice?
No — it's general information. Talk to a doctor about your own healthy weight.