Free Online BMI Calculator
Calculate your Body Mass Index (BMI) in seconds. Compare your score with official World Health Organization categories, discover your healthy weight range, and get AI-backed insights.
Great job! Your BMI is in the optimal range associated with lower risks of metabolic and cardiovascular conditions.
Official World Health Organization (WHO) BMI Categories
The World Health Organization establishes international BMI ranges for adult men and women aged 20 and over. Below is the clinical classification breakdown:
| BMI Range (kg/m²) | Category | Health Risk Profile |
|---|---|---|
| < 16.0 | Severe Thinness | Extremely high risk of malnutrition and bone density loss |
| 16.0 – 16.9 | Moderate Thinness | Elevated risk of nutrient deficiencies and immune suppression |
| 17.0 – 18.4 | Mild Thinness | Mild risk; recommended to increase calorie & protein intake |
| 18.5 – 24.9 | Normal / Healthy Weight | Lowest statistical risk of cardiovascular and metabolic illness |
| 25.0 – 29.9 | Overweight (Pre-obese) | Moderate risk of hypertension, dyslipidemia, and type-2 diabetes |
| 30.0 – 34.9 | Obese Class I | High risk of cardiovascular complications and sleep apnea |
| 35.0 – 39.9 | Obese Class II | Very high clinical risk requiring medical intervention |
| ≥ 40.0 | Obese Class III (Morbid) | Extremely high risk of severe health complications |
Beyond Scale Weight: Body Fat %
BMI only looks at height and weight. For muscular athletes, a high BMI might indicate muscle mass rather than excess body fat. Use our medically validated US Navy Body Fat Calculator to analyze your lean body mass versus fat mass ratio.
Go to Body Fat Calculator →Track Calories with AI Photo Scanner
Maintaining a healthy BMI requires balanced nutrition. With the BMI, Calorie & AI app, simply snap a picture of your meal to automatically detect protein, carbohydrates, and fats in 15+ languages.
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