Compare calculators
Both calculators run independently — change the inputs on either side to compare results.
BMI Calculator
Body Mass Index (BMI) is the most widely used screening tool for relating a person's weight to their height. It produces a single number that places adults into broad weight categories — underweight, healthy weight, overweight, or obese — and is used by the WHO, the CDC, and the NHS as a first-pass indicator of weight-related health risk. Enter your weight in kilograms and height in centimetres and the calculator returns your BMI in kg/m². The result is meant as a starting point for a conversation with a clinician, not a diagnosis on its own.
Ideal Weight Calculator
Estimates your ideal body weight in kilograms using four established clinical formulas — Hamwi, Devine, Robinson, and Miller — based on height and gender. Useful for setting realistic weight-loss or fitness goals.
Key differences
| BMI Calculator | Ideal Weight Calculator | |
|---|---|---|
| Category | Health | Health |
| Inputs required | 2 | 3 |
| Result | Your BMI | Ideal Body Weight (kg) |
| What it does | Body Mass Index (BMI) is the most widely used screening tool for relating a person's weight to their height. It produces a single number that places adults into broad weight categories — underweight, healthy weight, overweight, or obese — and is used by the WHO, the CDC, and the NHS as a first-pass indicator of weight-related health risk. Enter your weight in kilograms and height in centimetres and the calculator returns your BMI in kg/m². The result is meant as a starting point for a conversation with a clinician, not a diagnosis on its own. | Estimates your ideal body weight in kilograms using four established clinical formulas — Hamwi, Devine, Robinson, and Miller — based on height and gender. Useful for setting realistic weight-loss or fitness goals. |