BMI Calculator
Calculate your Body Mass Index (BMI) and determine if you're at a healthy weight.
Body Mass Index (BMI) is a measure of body fat based on height and weight that applies to adult men and women. It is calculated by dividing your weight by the square of your height.
While BMI is a useful screening tool, it does have limitations. It doesn't directly measure body fat or account for factors like muscle mass, bone density, or overall body composition.
- Underweight: BMI less than 18.5
- Normal weight: BMI between 18.5 and 24.9
- Overweight: BMI between 25 and 29.9
- Obesity (Class 1): BMI between 30 and 34.9
- Obesity (Class 2): BMI between 35 and 39.9
- Obesity (Class 3): BMI 40 or higher
How to Use This BMI Calculator
Our BMI calculator helps you determine if you're at a healthy weight based on your height and weight. Here's how to use it:
- Choose your preferred unit system (metric or imperial).
- Enter your height (in centimeters or feet/inches).
- Enter your weight (in kilograms or pounds).
The calculator will instantly show your BMI, weight category, healthy weight range, and recommendations for weight management.
Understanding BMI
Body Mass Index (BMI) is a numerical value calculated from your weight and height. It provides a simple way to classify weight status that may indicate whether you're at a healthy weight.
The formula for BMI is:
BMI = weight(kg) / height(m)²Or in imperial units:
BMI = 703 × weight(lb) / height(in)²BMI Categories
| BMI Range | Weight Category | Health Risk |
|---|---|---|
| Below 18.5 | Underweight | Increased risk for some health problems |
| 18.5 - 24.9 | Normal weight | Lowest risk for health problems |
| 25.0 - 29.9 | Overweight | Increased risk for heart disease, diabetes, and other conditions |
| 30.0 - 34.9 | Obesity (Class 1) | High risk for health problems |
| 35.0 - 39.9 | Obesity (Class 2) | Very high risk for health problems |
| 40.0 and above | Obesity (Class 3) | Extremely high risk for health problems |
Limitations of BMI
While BMI is a useful screening tool, it does have some limitations:
- It doesn't distinguish between fat, muscle, and bone mass.
- Athletes with high muscle mass may have a high BMI but low body fat.
- Older adults may have a healthy BMI but still have too much body fat.
- It doesn't account for where fat is stored in the body (abdominal fat poses higher health risks).
- It may not be accurate for pregnant or breastfeeding women, children, or certain ethnic groups.
For a more comprehensive assessment of your health, consult with a healthcare professional who can consider other factors like waist circumference, body composition, and lifestyle.
Tips for Maintaining a Healthy Weight
- Eat a balanced diet rich in fruits, vegetables, whole grains, and lean proteins.
- Limit processed foods, sugary drinks, and foods high in saturated fats.
- Stay physically active with at least 150 minutes of moderate exercise per week.
- Get adequate sleep (7-9 hours for most adults).
- Manage stress through relaxation techniques, meditation, or other activities you enjoy.
- Stay hydrated by drinking plenty of water throughout the day.
- Consider working with a healthcare provider, dietitian, or fitness professional for personalized guidance.