What is BMI?

Body Mass Index (BMI) is a simple calculation that estimates body fat based on your height and weight. It applies to both adult men and women.

Use the tool below to check your BMI instantly.

🔹 Enter your height and weight (standard or metric).
🔹 Click “Calculate BMI” to see your results.

BMI Calculator

Calculate your Body Mass Index in seconds

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What is BMI and why is it important?

BMI (Body Mass Index) is a measure of body fat based on height and weight. It helps determine whether you have a healthy weight, are underweight, overweight, or obese. While BMI is a useful guideline, it does not consider muscle mass or body composition.

How is BMI calculated?

The BMI formula is:
Metric system: BMI = weight (kg) / height² (m²)
Imperial system: BMI = (weight (lbs) / height² (in²)) × 703
Our calculator does this automatically for you!

What do BMI categories mean?

Underweight: BMI below 18.5
Normal weight: BMI 18.5 – 24.9
Overweight: BMI 25 – 29.9
Obese: BMI 30 or higher
However, BMI does not distinguish between muscle and fat, so always consult a healthcare professional for an accurate assessment.

Is BMI accurate for athletes and bodybuilders?

Not always. BMI does not differentiate between muscle and fat, so athletes with high muscle mass may be classified as overweight or obese, even if they have low body fat.

Can BMI be used for children?

BMI for children is measured differently than for adults, as it considers age and sex. Pediatric BMI percentiles are used instead of standard BMI categories.

How can I improve my BMI?

If your BMI is outside the healthy range, consider making small lifestyle changes:
Eat a balanced diet rich in whole foods.
Exercise regularly, including both cardio and strength training.
Monitor portion sizes and avoid excessive processed foods.
Always consult a doctor before starting a new fitness or nutrition plan.