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BMI Calculator

Calculate your Body Mass Index instantly. Understand what it means for your health.

Calculate Your BMI

Enter your height and weight for an instant result.

Under
<18.5
Normal
18.5-24.9
Over
25-29.9
Obese
30+

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What Is BMI?

Body Mass Index is a number calculated from your height and weight. It is used as a screening tool to identify possible weight problems in adults. It does not directly measure body fat but is a useful starting point.

BMI Categories

BMI RangeCategory
Below 18.5Underweight
18.5 – 24.9Normal weight
25.0 – 29.9Overweight
30.0 – 34.9Obese (Class I)
35.0 – 39.9Obese (Class II)
40.0 and aboveObese (Class III)

BMI Limitations

BMI does not account for muscle mass, bone density, or where fat is distributed in your body. Athletes often have a high BMI but low body fat. Always talk to a healthcare provider for a full assessment.

When To See a Provider

If your BMI is below 18.5 or above 25, a conversation with a healthcare provider is a good idea. Weight changes in either direction can affect your heart, blood sugar, joints, and energy levels.

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