BMI Calculator

Calculate your Body Mass Index (BMI) and get personalized health insights

Calculate Your BMI

Enter your measurements to calculate BMI

BMI Categories

Understanding your BMI result

Underweight

BMI less than 18.5

Normal weight

BMI 18.5 - 24.9

Overweight

BMI 25 - 29.9

Obese

BMI 30 or greater

Note: BMI is a screening tool and doesn't directly measure body fat. Consult with a healthcare provider for a comprehensive health assessment.

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About BMI Calculator

Body Mass Index (BMI) is a simple calculation using a person's height and weight. The formula is BMI = kg/m² where kg is a person's weight in kilograms and m² is their height in meters squared. BMI is used to screen for weight categories that may lead to health problems.

Understanding BMI Categories

  • Underweight (BMI < 18.5): May indicate malnutrition, eating disorder, or other health problems
  • Normal weight (BMI 18.5-24.9): Indicates a healthy weight range
  • Overweight (BMI 25-29.9): May increase risk of health problems
  • Obese (BMI ≥ 30): Significantly increases risk of serious health conditions

BMI Formulas

  • Metric: BMI = weight (kg) ÷ height² (m²)
  • Imperial: BMI = (weight (lbs) ÷ height² (inches²)) × 703

Limitations of BMI

While BMI is a useful screening tool, it has limitations:

  • Doesn't distinguish between muscle and fat mass
  • May not be accurate for athletes or very muscular individuals
  • Doesn't account for age, sex, or ethnicity differences
  • Doesn't measure body fat distribution
  • May not be accurate for elderly individuals

Health Risks by BMI Category

  • Underweight: Weakened immune system, osteoporosis, anemia
  • Overweight: Type 2 diabetes, high blood pressure, heart disease
  • Obese: Stroke, certain cancers, sleep apnea, joint problems

When to See a Doctor

If your BMI is outside the normal range, consider consulting with a healthcare provider. They can assess your overall health, body composition, and risk factors to provide personalized recommendations for achieving or maintaining a healthy weight.

Tips for Healthy Weight

  • Eat a balanced diet rich in fruits, vegetables, and whole grains
  • Exercise regularly (at least 150 minutes per week)
  • Get adequate sleep (7-9 hours per night)
  • Manage stress through healthy coping mechanisms
  • Stay hydrated by drinking plenty of water
  • Avoid crash diets and focus on sustainable lifestyle changes