Ideal Weight Calculator
Estimate your ideal body weight from height and sex using the clinically cited Devine formula.
Formula last reviewed 4 August 2026 · How we verify our calculators
Ideal body weight
70.5 kg
Updates live as you type
Frequently asked questions
It uses the Devine formula (1974): 50 kg for men or 45.5 kg for women, plus 2.3 kg for every inch of height above 5 feet (152.4 cm).
It was originally created for medication dosing and remains one of the most widely cited ideal-body-weight formulas in clinical settings.
Not exactly. Ideal body weight is a single reference figure; a healthy weight is a range that also depends on body composition, age and frame. Use BMI alongside this.
No. Like most height-based formulas, it ignores muscle mass and frame size, so athletes and larger-framed people may sit healthily above it.
Seventy and a half kilos at 175 centimetres
A man of 175 cm has an estimated ideal body weight of 70.5 kg under the Devine formula.
Men: 50 kg + 2.3 kg for each inch over 5 feet Women: 45.5 kg + 2.3 kg for each inch over 5 feet
175 cm is about 68.9 inches, or 8.9 inches over five feet: 50 + (2.3 × 8.9) = 70.5 kg.
What this formula was actually for
The Devine formula, published in 1974, was not developed to define a healthy body weight. It was created to calculate drug dosages — specifically for medications whose distribution depends on lean body mass rather than total weight, where dosing on actual weight in an obese patient would overdose them.
It remains widely used in clinical pharmacology for exactly that purpose. Its migration into general fitness advice is an accident of convenience rather than a validated application, and it explains several of the formula's oddities: the arbitrary 5-foot baseline, the linear increment, and the fixed 4.5 kg difference between men and women regardless of build.
Other formulas exist — Robinson (1983), Miller (1983), Hamwi (1964) — each giving slightly different answers from the same height, which is itself an indication that none is measuring something precise.
Why a single number is the wrong frame
The formula produces one value from one input. Real healthy weight depends on several things it cannot see:
Frame size. Skeletal width varies substantially between individuals of the same height, and a large-framed person can carry considerably more weight at the same body composition.
Muscle mass. The formula cannot distinguish muscle from fat. A trained individual frequently exceeds their "ideal" weight while carrying less fat than someone at it.
Age. Body composition changes across life, and slightly higher weight in older adults is associated with better outcomes, not worse.
Ethnicity. As with BMI, South Asian populations carry more body fat and more visceral fat at a given weight than European populations, so the same figure carries different metabolic implications.
A more useful frame is a healthy weight range rather than a point. Using the WHO BMI band of 18.5–24.9 at 175 cm gives roughly 56.6 to 76.3 kg. Applying the lower Asian-Indian thresholds of 18.0–22.9 gives about 55.1 to 70.1 kg — a meaningfully different range, and the more appropriate one for South Asian individuals.
Better measures to use alongside
Waist circumference, measured at the navel, which captures visceral fat — the fat that actually drives metabolic risk. Indian guidance flags risk above 90 cm for men and 80 cm for women.
Waist-to-height ratio — keeping your waist under half your height is simple, well-supported and works across ages and ethnicities.
Body fat percentage, if you have access to a reasonable measurement.
Trend over time, which is more informative than any single reading against any formula.
This is a general estimate and is not medical advice. It does not apply to children, pregnant women, or people with significant muscle mass, and it should not be used to set a weight-loss target without professional input.
Common mistakes
Treating it as a health target. It is a pharmacological dosing formula.
Applying it to athletes. Muscle mass breaks the assumption entirely.
Using it for children or during pregnancy. It does not apply.
Ignoring frame size. Skeletal variation is substantial at any height.
Preferring one number to a range. Healthy weight spans roughly 20 kg at this height.
Sources
- Devine BJ (1974) — "Gentamicin therapy," Drug Intelligence & Clinical Pharmacy (origin of the Devine formula, developed for medication dosing)