BMI Calculator

Calculate your Body Mass Index (BMI) to check if your weight is healthy for your height.

BMI Categories

BMI RangeCategory
< 18.5Underweight
18.5 - 24.9Normal weight
25 - 29.9Overweight
30 - 34.9Obese (Class I)
35 - 39.9Obese (Class II)
≥ 40Obese (Class III)

What is BMI?

Body Mass Index (BMI) is a simple calculation using height and weight to estimate body fat. It was developed by Belgian mathematician Adolphe Quetelet in the 1830s and is widely used as a screening tool for weight categories.

How is BMI Calculated?

The BMI formula is: BMI = weight (kg) / height² (m²)

For imperial units: BMI = (weight in lbs × 703) / height² (inches²)

Limitations of BMI

While BMI is useful, it has limitations:

  • Does not distinguish between muscle and fat mass
  • Athletes may have high BMI but low body fat
  • Does not account for age, gender, or ethnicity
  • Does not measure fat distribution (belly fat vs. other areas)
  • Not suitable for children, pregnant women, or elderly

Healthy Weight Tips

  • Maintain a balanced diet rich in fruits, vegetables, and whole grains
  • Exercise regularly - aim for 150 minutes of moderate activity per week
  • Stay hydrated and limit sugary drinks
  • Get adequate sleep (7-9 hours for adults)
  • Consult a healthcare provider for personalized advice