BMI Calculator
Calculate your Body Mass Index based on height and weight.
Body Mass Index (BMI) is one of the most widely used methods to assess whether a person has a healthy body weight relative to their height. Our free BMI calculator gives you instant, accurate results to help you understand your weight category and take steps toward better health.
What Is BMI?
BMI (Body Mass Index) is a numerical value derived from your weight and height. It was developed by Belgian mathematician Adolphe Quetelet in the 19th century and is now used globally by health professionals as a quick screening tool for weight-related health risks.
While BMI does not measure body fat directly, it correlates with more direct measures of body fat and provides a useful starting point for health assessments.
BMI Categories
The World Health Organization (WHO) defines the following BMI categories for adults:
| Underweight | Below 18.5 |
| Normal weight | 18.5 – 24.9 |
| Overweight | 25.0 – 29.9 |
| Obese (Class I) | 30.0 – 34.9 |
| Obese (Class II) | 35.0 – 39.9 |
| Obese (Class III) | 40.0 and above |
How to Calculate BMI
The BMI formula is straightforward. For the metric system: BMI = weight (kg) ÷ height (m)². For the imperial system: BMI = (weight (lbs) × 703) ÷ height (inches)².
For example, a person weighing 70 kg with a height of 1.75 m would have a BMI of 70 ÷ (1.75 × 1.75) = 22.9, which falls in the normal weight range.
Tips for Maintaining a Healthy BMI
Achieving and maintaining a healthy BMI involves a combination of balanced nutrition, regular physical activity, and healthy lifestyle habits.
- •Eat a balanced diet rich in fruits, vegetables, whole grains, and lean proteins
- •Engage in at least 150 minutes of moderate aerobic activity per week
- •Stay hydrated and limit sugary drinks
- •Get 7–9 hours of quality sleep each night
- •Monitor your weight regularly and adjust habits as needed
👉 Calculate your BMI now and take the first step toward understanding your health!
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