Estimated ideal weight

65.84

Computed from default inputs using graph `synth-ideal-weight-calculator`.

Height

170 cm

Range: 80 - 250

"Ideal body weight" formulas are linear height models, and this calculator shows its assumptions instead of hiding them: a base weight at 152.4 cm (5 feet) plus a fixed increment per centimeter above. The defaults — 50 kg base, 0.9 kg per cm — reproduce the Devine formula for men (50 kg + 2.3 kg per inch over 5 ft), published in 1974 for calculating drug doses, not for judging bodies. Set the base to 45.5 kg for Devine's female version, or 52 kg with 0.75 kg/cm to approximate Robinson's 1983 revision. That editability is the honest part: the competing formulas disagree with each other by 3–6 kg at ordinary heights, which is the strongest evidence that no single "ideal" exists. For a health-oriented target range, a BMI of 18.5–24.9 applied to your height² gives a band, not a point — usually more useful than any single-number formula.

Solve for Height

Height: 177.3173 for Estimated ideal weight 72.424

Height-based ideal weight estimate.

idealWeightKg= baseWeightKg+\max\left(0, heightCm-152.4\right)\cdot kgPerCm

idealWeightKgbaseWeightKg + max(0, heightCm - 152.4) * kgPerCm

Estimated ideal weight decision comparison

item	value	note
Stress low	50	Height: 80
Conservative	50	Height: 127.5
Downside	50.54	Height: 153
Base case	65.84	Height: 170
Upside	81.14	Height: 187.00000000000003

Visual Analysis1 series8 points

Expanded chart built from the same sensitivity run as the table, so users can read the trend and verify the numbers in one place.

Trend

Upward

Min

Max

82.2036

Insight

Estimated ideal weight shows an upward pattern, with a visible peak around 188.1818 at 82.2036.

Visual response curve for Estimated ideal weight.

Same height, three defensible numbers
At 180 cm: Devine (defaults) gives 50 + 27.6 × 0.906 = 75.0 kg. Robinson's coefficients (52 kg, 0.75 kg/cm) give 72.7 kg. The healthy-BMI band gives 60–80.7 kg. A person weighing 78 kg is "3 kg over ideal" by one formula, "5 kg over" by another, and comfortably inside the evidence-based range — a spread worth seeing before treating any one output as the truth.

Where does the 0.9 kg per cm come from?
It is Devine's 2.3 kg per inch converted to metric (2.3 ÷ 2.54 = 0.906). Robinson's revision used 1.9 kg per inch (0.75 kg/cm) with a 52 kg base for men, producing lower targets at tall heights. The adjustable slope on this page lets you reproduce either — or see how sensitive the "ideal" is to a coefficient chosen half a century ago.

Why do clinicians still use IBW if it isn't a health target?
Because its original purpose survives: drug dosing (some medications dose on ideal or adjusted rather than actual body weight), ventilator tidal-volume settings (calculated per kg of predicted body weight from height and sex), and nutrition calculations. In all of these, IBW is a standardized proxy for body size — a unit convention, not advice.

What is a better personal target than a single ideal weight?
A range: multiply height in meters squared by 18.5 and by 24.9 to bracket the conventional healthy-BMI band — for 175 cm, roughly 57 to 76 kg. Where in that band is right depends on build, body composition, and history; the band's width is the honest answer the single-number formulas paper over.

Health tools disclaimer: Educational estimates only, not medical advice, diagnosis, or treatment. For clinical decisions, dosing, or emergencies, follow guidance from US Department of Health & Human Services and a licensed professional in your jurisdiction.

Estimate ideal body weight from height with a configurable base weight and height increment.

Ideal Weight Calculator turns Height, Base weight at 152.4 cm, and Weight added per cm above 152.4 into Estimated ideal weight. Confirm the units and assumptions match your situation before relying on the result.

Enter a measured height. Use a measured height rather than a remembered one. The slope is 2.3 kg per inch, so a two-inch error shifts the target by more than 4 kg.
Select sex. Every formula in this family carries a different baseline for men and women — 50 kg versus 45.5 kg in Devine — applied at the same 5 ft anchor.
Choose the formula deliberately. Hamwi (1964), Devine (1974), Robinson (1983), and Miller (1983) differ in baseline and slope. Match the one your context expects — clinical dosing protocols usually specify Devine.
Read the output as one point estimate. The four formulas span nearly 5 kg at the same height. Treat the figure as a reference point produced by a named method, not as a measured or recommended weight.
Cross-check against the BMI band. Convert your height into the 18.5–24.9 BMI weight range and confirm the figure sits inside it. Where the two disagree — very short or very tall heights — the BMI band is the better guide.

Overwhelm from technical jargon

Start with the basic inputs only — advanced options can be explored once you understand the fundamentals. Important: Don't be discouraged if your results seem unfavorable — these tools help you plan, not judge.

Enter your values, then check the formula, scenarios, and FAQ to confirm the assumptions fit your case. For medical, financial, legal, or safety-critical decisions, treat the output as an estimate and verify it against the relevant professional standard.

World Health Organization. "Body mass index - BMI." WHO Regional Office for Europe, 2024.BMI classification thresholds: underweight <18.5, normal 18.5-24.9, overweight 25-29.9, obese ≥30
Centers for Disease Control and Prevention. "About Child & Teen BMI." CDC, 2024.Pediatric BMI uses age-sex-specific percentiles, not adult thresholds
Mifflin MD, St Jeor ST, et al. "A new predictive equation for resting energy expenditure in healthy individuals." Am J Clin Nutr. 1990;51(2):241-247.BMR formula: 10×weight(kg) + 6.25×height(cm) - 5×age - 161 (female) or +5 (male)
Institute of Medicine. "Weight Gain During Pregnancy: Reexamining the Guidelines." National Academies Press, 2009.Recommended pregnancy weight gain by pre-pregnancy BMI category

When is this health estimation context enough?
Use it when the result only depends on age, sex, height and no local rule changes the interpretation.

What should I record with the result?
Record the input values, reference population, measurement unit, activity estimate, output unit, and rounding rule used in the calculation.

When should I use a specialized modifier?
Use a specialized modifier when measurement units, reference range, age/sex context, and non-diagnostic limits materially changes how the same result should be explained.

Treating the output as a medical target. Devine's formula was built so hospital pharmacists could dose aminoglycoside antibiotics against lean body size; it was never validated as a weight to aim for. A muscular person can be healthy far above it, and reaching it is not itself a clinical goal.

Using the male default for everyone. The 50 kg base is Devine's male constant; the female version starts at 45.5 kg. Left unchanged, the calculator overstates the conventional female figure by 4.5 kg at every height — the single most common misuse of IBW formulas everywhere they appear.

Ideal Weight Calculator

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