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Both calculators run independently — change the inputs on either side to compare results.

Health

Ideal Weight Calculator

Estimate your "ideal" reference body weight from your height, biological sex, and body frame size using the Devine formula — originally created in 1974 for pharmacological dose calculation and still used clinically today. Useful as a rough planning anchor, but not a personal weight goal: it ignores muscle mass, age, and individual physiology.

Fill in the required fields to see your result.
Fitness

BMI Calculator

Calculate Body Mass Index (BMI) — body weight in kg divided by height in metres squared — to screen for under/overweight categories. The most widely used population-level fitness and health risk metric, with known limitations for athletes and unusual body compositions.

Underweight<18.5Normal18.5–25Overweight25–30Obese I30–35Obese II+35+
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Key differences

Ideal Weight CalculatorBMI Calculator
CategoryHealthFitness
Inputs required32
ResultIdeal Weight (kg)Your BMI
What it doesEstimate your "ideal" reference body weight from your height, biological sex, and body frame size using the Devine formula — originally created in 1974 for pharmacological dose calculation and still used clinically today. Useful as a rough planning anchor, but not a personal weight goal: it ignores muscle mass, age, and individual physiology.Calculate Body Mass Index (BMI) — body weight in kg divided by height in metres squared — to screen for under/overweight categories. The most widely used population-level fitness and health risk metric, with known limitations for athletes and unusual body compositions.