Ideal Weight Calculator
Estimate your ideal weight with four classic formulas
Ideal Weight by Formula
Healthy BMI Weight Range
Based on a healthy BMI of 18.5–25 for your height
Estimate your ideal body weight from four classic formulas — Devine, Robinson, Miller, and Hamwi — plus the healthy BMI weight range for your height. Enter your height in centimeters and pick your sex; the calculator converts your height to inches, applies each formula’s 5 ft base, and shows all four results side by side in kilograms. It is built for anyone setting a weight goal, checking a fitness plan, or just curious what the textbook formulas say.
How to Use
- Enter your height: Type your height in centimeters into the input field.
- Select your sex: Choose male or female — each formula uses different constants.
- Calculate: Click the calculate button to see all four formula results.
- Check the range: Compare the formulas with the healthy BMI weight range below them.
Features
- Four established formulas: Devine, Robinson, Miller, and Hamwi
- Healthy weight range derived from BMI 18.5–25
- Input validation with clear bounds (100–250 cm)
- Results rounded to one decimal place in kilograms
- Works entirely in your browser — your data never leaves the page
The Four Formulas Explained
All four formulas share the same structure: a base weight at 5 ft (60 in) plus a fixed increment per additional inch. Devine (1974) uses 50 kg + 2.3 kg/in for men and 45.5 kg + 2.3 kg/in for women, and remains the standard for medication dosing. Robinson (1983) refines it to 52 kg + 1.9 kg/in for men and 49 kg + 1.7 kg/in for women. Miller (1983) starts higher — 56.2 kg + 1.41 kg/in for men, 53.1 kg + 1.36 kg/in for women — producing flatter curves for tall people. Hamwi (1964) uses 48 kg + 2.7 kg/in for men and 45.5 kg + 2.2 kg/in for women, giving the steepest per-inch increase. Because they disagree by several kilograms at most heights, looking at all four together is more honest than trusting any single one.
Use Cases
- Goal setting: Pick a realistic target weight before starting a diet or training plan.
- Fitness tracking: Compare your current weight against formula-based references.
- Nutrition planning: Use the healthy BMI range as the weight input for calorie tools.
- Education: See how the classic clinical formulas differ from each other.
Reading the Results
Treat the four values as a cluster, not a verdict. If they span, say, 68–75 kg, that whole interval is a reasonable reference zone, and the healthy BMI range adds a second, independent check based on population data rather than clinical dosing rules. If you carry a lot of muscle, expect to sit above every estimate without being unhealthy; if you have a small frame, the lower end may fit better. These formulas were derived from adult populations and do not apply to children or teenagers.
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Frequently Asked Questions
Which ideal weight formula is the most accurate?
No single formula is universally best. Devine (1974) is the most widely used in clinical settings, while Robinson, Miller, and Hamwi adjust the base weight and per-inch increment. Showing all four side by side gives you a realistic range rather than a single rigid number.
Why do all formulas use a 5 ft base?
Each formula starts from a base weight at 5 ft (60 inches, about 152.4 cm) and adds a fixed number of kilograms for every inch above that. For heights below 5 ft the same increment is subtracted, so very short heights can produce less reliable estimates.
How is the healthy BMI weight range calculated?
The tool multiplies the healthy BMI bounds (18.5 and 25) by your height in meters squared. The result is the weight interval in kilograms that the World Health Organization classifies as a normal, healthy range for your height.
Do these formulas account for muscle mass or body frame?
No. These are statistical formulas based on height and sex only. They do not consider muscle mass, bone density, age, or body frame size, so athletes and very muscular people may weigh more than the estimate while still being healthy.
Is this calculator a substitute for medical advice?
No. The results are general estimates for adults and are not medical advice. For personal health decisions — especially during pregnancy, illness, or eating-disorder recovery — consult a doctor or registered dietitian.