Calculate your Body Mass Index (BMI) to check your healthy weight range.
📊 BMI Quick Reference
< 18.5
Underweight
18.5 - 24.9
Normal
25.0 - 29.9
Overweight
≥ 30.0
Obese
Complete Body Mass Index (BMI) Guide
Body Mass Index (BMI) is a measurement calculated using an individual's weight and height. This index is a widely used screening tool that categorizes individuals into various weight categories including underweight, normal weight, overweight, and obese.
📊 BMI Calculation
Metric System (kg, m)
BMI = Weight(kg) ÷ Height(m)²
Example: 70kg, 175cm → 70 ÷ (1.75)² = 22.9
Imperial System (lbs, in)
BMI = (Weight(lbs) × 703) ÷ Height(in)²
Example: 154lbs, 69in → (154 × 703) ÷ (69)² = 22.7
📋 BMI Interpretation
Underweight
BMI < 18.5
Risk of malnutrition
Normal Weight
BMI 18.5–24.9
Healthy weight range
Overweight
BMI 25–29.9
Increased health risks
Obese
BMI ≥ 30
Serious health risks
Obesity Classification Stages
Class I Obesity
BMI 30–34.9
Class II Obesity
BMI 35–39.9
Class III Obesity (Severe)
BMI ≥ 40
💡 Health Implications by BMI Range
📉 Underweight (BMI < 18.5)
Being underweight may indicate malnutrition, eating disorders, or other health problems.
- Nutritional deficiencies
- Risk of osteoporosis
- Weakened immune system
- Irregular menstruation (women)
✅ Normal Weight (BMI 18.5–24.9)
Indicates a healthy weight range for most people.
- Lower risk of heart disease
- Reduced diabetes risk
- Overall good health status
- Life expectancy benefits
⚠️ Overweight (BMI 25–29.9)
Being overweight can increase the risk of various health problems.
- High blood pressure
- Type 2 diabetes
- Heart disease
- Increased risk of certain cancers
🚨 Obese (BMI ≥ 30)
Obesity increases the risk of various serious health problems.
- Cardiovascular disease
- Type 2 diabetes
- Sleep apnea
- Joint disorders
- Certain cancers (breast, colorectal, etc.)
- Depression
⚖️ BMI Limitations
Muscle Mass Not Considered
Athletes or people with high muscle mass may have elevated BMI readings
Fat Distribution
Does not account for fat location, such as abdominal obesity
Individual Differences
Cannot fully reflect differences by age, gender, and ethnicity