BMI Calculator
Body mass index
Calculate your Body Mass Index (BMI) from weight and height. Enter your weight in kg and height in cm to get your BMI and category (underweight, normal, overweight, obese). Free tool—no signup. Use for health awareness only; consult a doctor for medical advice. Works in your browser, private by design.
BMI Calculator
How the BMI Calculator Works
- Enter your weight in kilograms (kg) and height in centimeters (cm). Use a scale and measuring tape for accuracy.
- The tool calculates BMI using the formula: weight ÷ (height/100)². Results update instantly as you type.
- View your BMI number and category: Underweight (below 18.5), Normal (18.5–24.9), Overweight (25–29.9), or Obese (30+).
- Use results for general health awareness only. BMI does not account for muscle mass, age, or ethnicity. Consult a doctor for medical advice.
Why Use This Calculator?
BMI is a widely used screening tool for weight-related health risks. While it has limitations—it doesn't distinguish muscle from fat—it provides a quick, free way to check if your weight is in a healthy range. Doctors and health organizations use BMI for population studies and initial assessments. This calculator runs entirely in your browser; your measurements never leave your device.
Understanding BMI
BMI (Body Mass Index) is weight in kg divided by height in meters squared. It correlates with body fat for most adults.
Underweight (below 18.5) may indicate malnutrition or other conditions. Normal range (18.5–24.9) is associated with lower health risks.
Overweight (25–29.9) and obese (30+) are linked to higher risk of heart disease, diabetes, and other conditions. Lifestyle changes can help.
BMI does not apply to children, pregnant women, or very muscular athletes. Waist circumference and body composition offer additional insight.
Frequently Asked Questions
Common Use Cases
- ✓Health screening
- ✓Weight management
- ✓Fitness tracking
- ✓Medical checkups