BMI Calculator
Body Mass Index Calculator – Know Your Health Status
Metric Units
Imperial Units
Understanding Body Mass Index (BMI)
What is BMI?
Body Mass Index (BMI) is a simple calculation using your height and weight to estimate body fat. It’s a screening tool that helps identify potential weight problems in adults. While not a direct measurement of body fat, BMI correlates with more direct measures of body fat and offers a quick assessment of weight categories that may lead to health problems.
BMI Limitations
BMI has some limitations as it doesn’t directly measure body fat or account for muscle mass, bone density, or fat distribution. Athletes may have a high BMI due to increased muscle mass rather than fat. Older adults may have more body fat than younger adults with the same BMI. Always consult with a healthcare provider for a comprehensive health assessment.
BMI Categories and Health Risks
| Category | BMI Range | Health Risk |
|---|---|---|
| Underweight | Below 18.5 | Nutritional deficiency, osteoporosis |
| Normal weight | 18.5 – 24.9 | Lowest risk (healthy range) |
| Overweight | 25 – 29.9 | Moderate risk of chronic diseases |
| Obesity Class I | 30 – 34.9 | High risk |
| Obesity Class II | 35 – 39.9 | Very high risk |
| Obesity Class III | 40 and above | Extremely high risk |
When to See a Doctor
Consult a healthcare provider if your BMI falls outside the normal range, or if you have concerns about your weight. They can perform additional assessments like waist circumference measurements, body fat analysis, and evaluate other risk factors for diseases associated with obesity.
Maintaining Healthy Weight
Achieving and maintaining a healthy weight includes eating a balanced diet, regular physical activity (150 minutes of moderate exercise weekly), adequate sleep (7-9 hours nightly), and stress management. Small, sustainable changes often lead to long-term success rather than drastic diets.
BMI Calculation Formulas
Metric Formula
BMI = weight (kg) ÷ (height (m))²
Example: 70kg ÷ (1.7m × 1.7m) = 24.2
Imperial Formula
BMI = [weight (lbs) ÷ (height (in))²] × 703
Example: [154lbs ÷ (67in × 67in)] × 703 = 24.1