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BMI Calculator — Body Mass Index

Inputs

🚻 Sex (optional)

📏 Height

⚖️ Weight

All results update instantly as you type.

Live results

BMI —

BMI Prime —

Category —

Healthy weight range —

Enter your height and weight to see your results.

🧮 Step-by-step derivation

—

Reference (adult BMI categories)

Category	BMI (kg/m²)
Underweight	< 18.5
Healthy weight	18.5 – < 25
Overweight	25 – < 30
Obesity (Class 1)	30 – < 35
Obesity (Class 2)	35 – < 40
Obesity (Class 3)	≥ 40

Cut-offs shown are standard adult thresholds. BMI is a screening tool only and doesn’t account for body composition.

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