About the Ideal Weight Calculator
This ideal weight calculator answers the question “how much should I weigh for my height?” using the four formulas clinicians and dietitians most often quote: Devine, Robinson, Miller and Hamwi. Each one starts from a base weight at 5 feet and adds a fixed amount for every inch above that, with separate values for men and women.
Because the formulas disagree by several pounds, you also get the average of the four and the full healthy weight range from BMI 18.5–24.9 at your height, which is the broader range most public-health guidance uses. Together they give a sensible target zone rather than a single “perfect” number.
Ideal body weight formulas were designed mainly for drug dosing and nutrition planning in adults, not as personal goals. They ignore frame size, muscle mass and age, so a muscular or large-framed person can be perfectly healthy above them. They are least reliable for people under 5 feet tall.
With the default inputs, the ideal weight (devine) is 160.9. Change any value above to recalculate instantly.
How to use the ideal weight calculator
- 1Select your sex.
- 2Choose US or metric units.
- 3Enter your height.
- 4Compare the four formula results and their average.
- 5Use the healthy BMI range as the wider target zone.
Formula and method
Each formula takes a base weight for someone exactly 5 feet (60 inches) tall and adds a fixed number of kilograms per inch of height above that. Devine (1974) was created for drug dosing and remains the clinical standard for “ideal body weight”; Robinson and Miller (both 1983) re-fitted the numbers to population data and give lower weights for taller people; Hamwi (1964) is an older dietetics rule of thumb.
Heights are converted to inches first (1 in = 2.54 cm), and results are converted to pounds at 2.2046 lb per kg for US units. The healthy BMI range multiplies 18.5 and 24.9 by your height in metres squared (the CDC defines healthy weight as a BMI of 18.5 to less than 25). All weight results are shown in pounds when you choose US units and in kilograms when you choose metric.
- base
- Weight in kg at a height of 5 ft (60 in)
- kg/in
- Kilograms added per inch of height above 5 ft
Worked examples
Man, 5 ft 10 in
He is 10 inches over 5 ft. Devine gives 50 + 2.3 × 10 = 73 kg (160.9 lb); Robinson 71 kg (156.5 lb); Miller 70.3 kg (155.0 lb); Hamwi 75 kg (165.3 lb). A healthy BMI at his height spans about 129–174 lb.
Woman, 165 cm (metric)
165 cm is 64.96 inches, or 4.96 inches over 5 ft. Devine: 45.5 + 2.3 × 4.96 ≈ 56.9 kg. The other formulas give 56.4–59.8 kg, all well inside the healthy BMI range of 50.4–67.8 kg.
Man, 6 ft 2 in
At 74 inches he is 14 inches over 5 ft, so Devine gives 50 + 2.3 × 14 = 82.2 kg, about 181.2 lb. Averaging all four formulas gives roughly 177.8 lb, because Robinson and Miller add less per inch for tall men.
Frequently asked questions
Which ideal weight formula is most accurate?+
None is “accurate” for an individual because none accounts for muscle or frame size. Devine is the most widely used in medicine, mainly for drug dosing. For a personal goal, the healthy BMI range combined with waist size is usually more useful.
How much should I weigh for my height?+
A practical answer is any weight that keeps your BMI between 18.5 and 24.9 — for example about 125–168 lb at 5 ft 9 in. The formula results give a narrower point estimate within or near that range.
Does ideal weight depend on age?+
These formulas do not change with age. Some research suggests slightly higher BMIs are not linked to higher mortality in older adults, so doctors may accept a somewhat higher weight in people over 65.
Why is my ideal weight lower than I expected?+
The formulas were derived decades ago from limited data and do not credit muscle mass. If you strength train or have a large frame, a weight above the formula result can be perfectly healthy; check body fat percentage for a better picture.
What is ideal body weight used for in hospitals?+
Clinicians use ideal body weight (usually Devine) to dose some drugs, set ventilator tidal volumes and estimate nutrition needs, because those depend on lean tissue rather than total weight.
This tool gives general estimates and is not medical advice. Talk to a doctor or qualified professional about your health, diet or training.