Ideal Weight Calculator
Free ideal weight calculator using the Devine, Robinson, Miller, and Hamwi formulas. Find your healthy weight range from height and gender, in cm or ft/in.
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Discover Your Ideal Body Weight
What is a healthy weight for your height? This calculator runs four peer-reviewed ideal body weight (IBW) formulas—Devine, Robinson, Miller, and Hamwi—side by side, then averages them and cross-checks the result against the BMI-based healthy range. Instead of a single number it gives you a realistic target zone, in kilograms, from just your height and gender.
Understanding Ideal Weight Formulas
Ideal body weight is an estimate of a healthy weight for a given height, first devised for clinical drug dosing. Each formula shares the same shape—a base weight at 5 feet (60 inches) plus a per-inch increment above that—but was fitted to a different population, so they disagree by a few kilograms. Devine (1974) is the clinical standard; Robinson (1983) and Miller (1983) refined it on newer data; Hamwi (1964) is the oldest and gives the widest spread. Averaging the four, and comparing them to the BMI 18.5–24.9 range, is more realistic than trusting any single formula.
Devine Formula (men)
IBW = 50 kg + 2.3 kg × (height in inches − 60). Women: 45.5 kg + 2.3 kg × (height in inches − 60).How to Use the Calculator
Select your gender.
Enter your height and pick cm, ft, or in.
Read the average ideal weight and the formula range.
Compare the four formulas and the BMI-based healthy range.
Uses for Ideal Weight
Fitness Goals
Set a realistic weight target zone rather than an arbitrary number.
Medical Consultations
Bring an IBW reference to discuss with your doctor or dietitian.
Medication Dosing Reference
Many drug doses use ideal body weight; the Devine formula is the clinical standard.
Progress Tracking
Compare your current weight against the ideal range over time.
Why Calculate Your Ideal Weight?
Four Formulas, One View
See Devine, Robinson, Miller, and Hamwi side by side instead of picking one blindly.
Realistic Target Zone
Get a healthy weight range and average, not a single misleading number.
Cross-Checked With BMI
Compare the formula results against the BMI 18.5–24.9 healthy range for your height.
Metric or Imperial
Enter your height in cm, feet, or inches—results are shown in kilograms either way.
Frequently Asked Questions
At 5'6" (168 cm), the four formulas put ideal weight at roughly 59–65 kg (130–143 lb) for a woman and about 63–68 kg (139–150 lb) for a man. The BMI 18.5–24.9 healthy range for that height is about 52–70 kg (115–154 lb), which is wider—use the formula average as a mid-point target within that band.
They differ only in their base weight and per-inch increment. Devine (1974) is the most widely used, especially clinically for drug dosing. Robinson (1983) and Miller (1983) were refitted on later data and tend to read a little lower. Hamwi (1964) is the oldest and gives the widest range. Rather than choosing one, use the average of all four—which is exactly what this calculator highlights.
Yes. These formulas depend only on height and gender, so they don't account for a large or small frame, age, or a muscular build. Athletes and muscular people are often healthy above these ranges because muscle weighs more than fat. For those cases a body-fat percentage or FFMI assessment is more informative than IBW alone.
Each was developed at a different time on a different study population, so their base weights and slopes differ. The spread between them—shown here as a range—is the point: it reflects genuine uncertainty in what 'ideal' means, so a target zone is more honest than a single figure.