Ideal Weight Calculator
'Ideal weight' sounds like one number, but the two formulas behind the phrase disagree on purpose. The Devine formula - 50 kg for a man plus 2.3 kg per inch over five feet - was built in 1974 to dose medications, and became the classic single answer. The healthy-BMI band (18.5-24.9) is wider because bodies are. This calculator shows both, side by side, in kg or lb, so you can see the range instead of worshipping a point.
The note under the result is the differentiator: no formula knows your frame, muscle mass or history, and an athletic body at the top of the BMI band can be healthier than a sedentary one at the bottom. Treat the band as a range, the trend as the signal, and your doctor as the tiebreaker - that is the honest version of this tool, and it's remembered here for your next check-in.
How to use
- Choose units (cm/kg or ft-in/lb), sex and enter your height.
- See the Devine ideal weight and the healthy-BMI range together.
- Use the band, not the point - and compare against where you were last month.
Frequently asked questions
What is the Devine ideal weight formula?
Men: 50 kg + 2.3 kg per inch over 5 feet. Women: 45.5 kg + the same inch allowance. It was published in 1974 to convert height into a medication dose, inherited from insurance tables, and became the 'ideal body weight' in medical texts - useful as a rough midpoint, never as a verdict on a body.
What is a healthy weight range for my height?
The BMI band 18.5-24.9 applied to your height: for 175 cm that's roughly 57-76 kg (126-168 lb). It's wide because it needs to be - bone structure, muscle and fat distribution vary enormously within one height. The calculator shows both the band and the Devine point so you can see the difference between a range and a myth.
Why does the calculator show a range instead of one number?
Because single-number ideals do real harm: they ignore frame size, muscle (which is denser than fat) and age. Research consistently finds the lowest mortality in the upper part of the 'normal' BMI band and slightly above it in older adults - the truth is a plateau, not a peak, and pretending otherwise just fuels yo-yo dieting.
Is BMI itself reliable?
As a population screen, yes; as an individual verdict, it's blunt - muscular people read as overweight, and 'normal BMI' can hide high body fat. Better signals: waist-to-height ratio (under about 0.5), how your clothes fit over months, and bloodwork. This tool starts the conversation; your clinician finishes it.