Find your ideal and healthy weight range using five different formulas plus Australian BMI guidelines. Results shown in kg and lbs.
Ideal weight is an estimate of a healthy body weight for your height and sex. There is no single "perfect" number — instead, several formulas (Devine, Robinson, Miller, Hamwi) give a healthy range. For most adults this range spans several kilograms, and your best target within it depends on your build, muscle mass and overall health.
| Formula | Ideal Weight (kg) | Ideal Weight (lbs) |
|---|
The classic ideal-weight formulas all start from a base weight at 152 cm (5 feet) of height, then add a set amount for each centimetre or inch above that. They differ only in those base numbers.
These are approximate healthy weight ranges based on a BMI of 18.5–24.9. Use them as a guide alongside the formula results above.
| Height | Healthy Range (Women) | Healthy Range (Men) |
|---|---|---|
| 160 cm (5'3") | 47–64 kg | 50–66 kg |
| 165 cm (5'5") | 50–68 kg | 53–70 kg |
| 170 cm (5'7") | 53–72 kg | 56–74 kg |
| 175 cm (5'9") | 57–76 kg | 60–78 kg |
| 180 cm (5'11") | 60–81 kg | 63–83 kg |
| 185 cm (6'1") | 63–85 kg | 67–88 kg |
The formulas were created in different decades for different purposes (originally for medication dosing), so their base weights vary. None accounts for muscle, frame size or body fat — which is their main limitation.
| Formula | Year | Tends To Give |
|---|---|---|
| Hamwi | 1964 | Higher estimates |
| Devine | 1974 | The common default |
| Robinson | 1983 | Slightly lower |
| Miller | 1983 | Lowest estimates |
Because none of these formulas measures body composition, treat the result as a healthy range to aim within, not a strict target.
Various formulas exist for estimating "ideal" body weight. Each was developed for different purposes and populations. No single formula is universally accurate — they serve as general guides rather than precise targets.
| Formula | Developed by | Original purpose |
|---|---|---|
| Devine | B.J. Devine, 1974 | Drug dosage calculations |
| Robinson | Robinson et al., 1983 | Medical dosing |
| Miller | Miller et al., 1983 | Drug dosing |
| Hamwi | G.J. Hamwi, 1964 | Diabetic diet planning |
| BMI Range | WHO / ABS | Population health screening |
The Australian Institute of Health and Welfare (AIHW) uses BMI 18.5–24.9 as the healthy weight range for adults. However, for people of Asian background, health risks may increase at lower BMI values (BMI ≥ 23 considered overweight in some guidelines).
The "ideal" weight is just one metric. The AIHW recommends considering waist circumference, fitness level, muscle mass, and metabolic health markers (blood pressure, cholesterol, blood glucose) alongside body weight for a complete health picture.
Select your sex, enter your height and current weight, and choose your frame size (small, medium, or large). Click Calculate to see your ideal weight estimate from five different formulas, your BMI-based healthy weight range, and how your current weight compares.
Wrap your thumb and middle finger around your wrist just below the wrist bone. If they overlap, you likely have a small frame. If they just touch, medium. If there is a gap between them, large frame. This simple test isn't precise but gives a reasonable starting point for selecting frame size in the calculator.
Each ideal weight formula was developed in a different decade for a different clinical purpose, so they produce different results — sometimes by several kilograms. As a practical guide, the spread between the lowest and highest formula results gives you a reasonable healthy weight range to aim for rather than a single target number.
| Formula | Ideal weight (Male, 175cm) |
|---|---|
| Devine (1974) | 70.0 kg |
| Robinson (1983) | 68.1 kg |
| Miller (1983) | 72.4 kg |
| Hamwi (1964) | 72.7 kg |
| BMI range (18.5–24.9) | 56.7–76.3 kg |
The practical takeaway: for a 175cm male, anywhere from about 68–76kg covers all formula estimates and the full BMI healthy range. The exact number matters much less than being consistently within this broad zone while feeling healthy and energetic.
Standard ideal-weight formulas assume a medium build. Your frame size — small, medium or large — shifts where in the range your healthy weight sits. A simple check is to wrap your thumb and index finger around your wrist:
A more precise method measures wrist circumference relative to height. Either way, frame size explains why two people of the same height can both be at a healthy weight while weighing several kilograms apart — larger-framed people carry more bone and supporting tissue.
Multiple formulas (Devine, Robinson, Miller, Hamwi) estimate ideal weight from height and sex. Each gives slightly different results. The calculator shows all side by side so you can see the range rather than relying on a single figure.
Each was developed in a different decade for a different clinical purpose (primarily medication dosing) using different population samples. The spread reflects genuine uncertainty about what 'ideal' means for diverse individuals.
Yes. A larger-framed person healthily carries weight at the higher end of any formula's range. The wrist test gives a rough frame estimate: thumb and middle finger overlapping = small; touching = medium; gap = large.
A healthy weight depends on your height and sex. As a guide, a BMI of 18.5–24.9 gives the range — for example, about 53–72 kg at 170 cm. The calculator above shows both the formula estimates and the BMI-based range so you can see your healthy target.
Enter your height and sex in the calculator and it applies four formulas (Devine, Robinson, Miller, Hamwi) plus the BMI range. Each starts from a base weight at 5 feet of height and adds a set amount per inch above that, giving a healthy range rather than a single number.
Yes. At the same height, the formulas set a lower base weight for women than men, reflecting average differences in build and muscle mass. That is why a woman’s ideal weight range sits a little below a man’s of the same height.
They were created in different decades, originally to help calculate medication doses, so their base weights differ. None accounts for muscle or frame size. Seeing several results side by side gives you a realistic healthy range instead of one potentially misleading figure.
No. Ideal-weight formulas use only height and sex, so a very muscular person may sit above their "ideal" weight while being perfectly healthy. Pair the result with body fat percentage or waist measurement for a fuller picture.
Aim for gradual change through balanced eating and regular activity rather than extreme diets. A sustainable pace is about 0.25–0.5 kg per week. If you have a significant amount to lose or any health conditions, speak with a GP or dietitian for a personalised plan.