Compare calculators
Both calculators run independently — change the inputs on either side to compare results.
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.
Body Fat Percentage Calculator
Estimate your body fat percentage from a tape measure using the US Navy circumference method — the same protocol the US military uses for fitness compliance. Enter your waist, neck, height (and hip if female) and the calculator returns body fat percentage, accurate to within ±3–4 percentage points compared to a DEXA scan.
Key differences
| Ideal Weight Calculator | Body Fat Percentage Calculator | |
|---|---|---|
| Category | Health | Fitness |
| Inputs required | 3 | 5 |
| Result | Ideal Weight (kg) | Body Fat Percentage (%) |
| What it does | 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. | Estimate your body fat percentage from a tape measure using the US Navy circumference method — the same protocol the US military uses for fitness compliance. Enter your waist, neck, height (and hip if female) and the calculator returns body fat percentage, accurate to within ±3–4 percentage points compared to a DEXA scan. |