BMI Calculator
Calculate your Body Mass Index (BMI), a measure of body fat based on height and weight that applies to adult men and women.
About BMI
Body Mass Index (BMI) is a simple index of weight-for-height that is commonly used to classify underweight, overweight and obesity in adults. The calculation method differs based on the unit system used:
Metric Formula
BMI = weight (kg) / height² (m²)
Example:
Height: 175 cm (1.75 m)
Weight: 70 kg
BMI = 70 / (1.75 × 1.75) = 22.9
Imperial Formula
BMI = 703 × weight (lb) / height² (inches²)
Example:
Height: 69 inches (5'9")
Weight: 154 lb
BMI = 703 × 154 / (69 × 69) = 22.7
Underweight: BMI less than 18.5
May indicate nutritional deficiency or other health conditions. Consider consulting a healthcare provider.
Normal Weight: BMI 18.5 to 24.9
Generally indicates a healthy weight range. Maintain a balanced diet and regular physical activity.
Overweight: BMI 25 to 29.9
May increase risk of health issues. Consider lifestyle modifications and consult healthcare providers.
Obese: BMI 30 or greater
Higher risk for various health conditions. Recommended to seek professional medical advice.
Did You Know?
BMI was developed by Belgian mathematician Lambert Adolphe Jacques Quetelet in the 1830s. It was originally known as the Quetelet Index until it was termed Body Mass Index by Ancel Keys in 1972. Despite its age, it remains one of the most widely used diagnostic tools for identifying weight problems within populations.
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Note: While BMI is a useful screening tool, it is not diagnostic of body fatness or health. Factors such as age, sex, ethnicity, and muscle mass can influence the relationship between BMI and body fat. For a complete assessment of your health status, please consult with healthcare professionals.