Ideal Weight Calculator
Enter your height and sex to compare your ideal body weight from four classic formulas — Devine, Robinson, Miller, and Hamwi — side by side, plus a BMI-based healthy range. Metric or imperial, no submit button, no sign-up, and your numbers never leave your browser.
What is the Ideal Weight Calculator?
This ideal weight calculator estimates a target body weight for your height and sex using four classic clinical formulas at the same time: Devine, Robinson, Miller, and Hamwi. Instead of giving you one number from one formula, it lines all four up so you can see the realistic spread, and it adds a BMI-based healthy weight range for extra context. You enter a couple of values and read the results.
Everything is calculated locally in your browser, so your height, sex, and weight never leave your device. There is no account to create and no data saved — close the tab and your numbers are gone.
How to use it
- Pick your unit system: Metric (centimetres and kilograms) or Imperial (feet, inches, and pounds). The toggle switches every input and result at once.
- Choose your sex, then enter your height. The four formula results and the BMI healthy range update the instant you type — there is no submit button to press.
- Optionally enter your current weight to see how far you are from each formula's target, then read the comparison table and move on.
The formulas behind it
Every classic ideal body weight formula has the same shape: a base value at five feet of height plus a fixed amount for each inch above five feet. They differ only in the base and the per-inch step, and each has separate values for men and women.
- Hamwi (1964) — men 48.0 kg + 2.7 kg per inch over 5 ft; women 45.5 kg + 2.2 kg per inch.
- Devine (1974) — men 50.0 kg + 2.3 kg per inch over 5 ft; women 45.5 kg + 2.3 kg per inch.
- Robinson (1983) — men 52.0 kg + 1.9 kg per inch over 5 ft; women 49.0 kg + 1.7 kg per inch.
- Miller (1983) — men 56.2 kg + 1.41 kg per inch over 5 ft; women 53.1 kg + 1.36 kg per inch.
The BMI-based range is computed separately as the weights that put you between a BMI of 18.5 and 24.9 for your height, using weight equals BMI times height in metres squared.
Examples
- A man who is 5 ft 10 in (178 cm) gets formula results of roughly 70 to 75 kg, with a BMI healthy range near 58 to 79 kg.
- A woman who is 165 cm (about 5 ft 5 in) sees the four formulas cluster near 54 to 58 kg, while the BMI healthy range spans roughly 50 to 68 kg.
- Someone exactly 5 ft (152 cm) sits at each formula's base value, since there are no inches over five feet to add.
Common use cases
- Setting a realistic target before starting a diet or training plan.
- Sanity-checking a single number you saw on another site by comparing four formulas at once.
- Filling in a health or insurance form that asks for an ideal or target body weight.
- Switching unit systems when a clinician, app, or chart uses the one you are less used to.
Why use this ideal weight calculator
Most ideal weight calculators show a single formula and call it the answer, which hides how much these formulas disagree. This one shows Devine, Robinson, Miller, and Hamwi together so you see the real range, and it pairs them with a BMI-based healthy span so a single point estimate is never read in isolation. Metric and imperial share one toggle, the results are live with no submit button, and the entire calculation runs in your browser.
It is part of a small set of everyday health calculators. The BMI Calculator turns height and weight into a body mass index and weight category, and the TDEE Calculator estimates the calories you burn in a day so you can plan around a target.
Important note
This tool is for general reference and information only and is not medical advice or a diagnosis. Ideal body weight formulas are old clinical estimates that ignore body composition, frame size, and muscle, so they can be misleading for athletes, very muscular people, older adults, pregnant people, and children. For decisions about your health, consult a qualified healthcare professional.
Frequently asked questions
Which ideal weight formula is the most accurate?
There is no single best one. Devine, Robinson, Miller, and Hamwi were each built for different clinical purposes and give slightly different numbers. Comparing all four shows a realistic range rather than one exact figure, which is why this calculator displays them side by side.
Why does the calculator ask for my sex?
All four classic formulas use different base values and per-inch increments for men and women, because average frame and body composition differ. Selecting your sex applies the correct coefficients to every formula.
Is ideal body weight the same as a healthy weight?
Not exactly. Ideal body weight is a single target produced by an old clinical formula, while a healthy weight is a range. That is why this tool also shows the BMI-based healthy range (BMI 18.5 to 24.9) for your height alongside the formula results.
Does this ideal weight calculator store my data?
No. Every calculation runs locally in your browser. Your height, sex, and weight are never uploaded, saved, or shared, and there is no account to create.
What if I am shorter than five feet?
The classic formulas were defined for heights above five feet, with a base value at exactly five feet. Below that the calculator clamps to the base value rather than returning an unrealistic or negative number, so treat very short heights as approximate.