BMI Calculator
Calculate your Body Mass Index and get personalized AI insights about your health and recommended actions.
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AI Health Insight
BMI Categories
| BMI Range | Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 - 24.9 | Normal weight |
| 25.0 - 29.9 | Overweight |
| 30.0 and above | Obese |
Your Stats
Frequently Asked Questions
Body Mass Index (BMI) is a measure that uses your height and weight to estimate if you're at a healthy weight. It's calculated by dividing your weight in kilograms by your height in meters squared: BMI = kg/m². While it's a useful screening tool, it doesn't directly measure body fat or account for muscle mass.
BMI has several limitations: (1) It doesn't distinguish between muscle and fat - athletes may have high BMI but low body fat, (2) It doesn't account for age, sex, or ethnicity, (3) It doesn't show where fat is distributed - belly fat is more dangerous than fat elsewhere, (4) It's less accurate for elderly people who may have lost muscle mass.
For most adults, a healthy BMI is between 18.5 and 24.9. However, the optimal BMI may vary based on ethnicity. For example, Asians may have higher health risks at lower BMI levels, so some guidelines suggest a healthy range of 18.5-23 for Asian populations.
To lower your BMI healthily: (1) Create a moderate calorie deficit of 500-750 calories/day, (2) Increase physical activity - aim for 150+ minutes of moderate exercise weekly, (3) Eat more protein and fiber to stay full, (4) Reduce processed foods and sugary drinks, (5) Get adequate sleep (7-9 hours), (6) Manage stress. Aim to lose 1-2 pounds per week for sustainable results.
For children and teens (ages 2-19), BMI is calculated the same way but interpreted differently using age and sex-specific percentiles. A child's BMI is compared to others of the same age and sex. The categories are: Underweight (below 5th percentile), Healthy weight (5th-85th), Overweight (85th-95th), and Obese (95th and above).
Understanding Your BMI
BMI is a widely used screening tool to identify potential weight problems in adults. While it's not a diagnostic tool, it can indicate whether you might need further assessment.
Health Risks by BMI Category:
- Underweight (BMI < 18.5): Increased risk of malnutrition, osteoporosis, decreased immune function
- Normal (BMI 18.5-24.9): Lowest risk of weight-related health issues
- Overweight (BMI 25-29.9): Increased risk of heart disease, type 2 diabetes, high blood pressure
- Obese (BMI 30+): High risk of serious health conditions including heart disease, stroke, certain cancers
Better Indicators to Consider:
- Waist circumference: Men > 40 inches, Women > 35 inches indicates higher risk
- Waist-to-hip ratio: A more accurate predictor of health risks
- Body fat percentage: Directly measures fat vs. muscle
- Blood tests: Cholesterol, blood sugar, and other markers