Body Mass Index (BMI) is a widely used measurement to assess an individual's body weight relative to their height. BMI is calculated by dividing a person's weight in kilograms by the square of their height in meters.

The formula is BMI = weight (kg) / (height (m) * height (m)).

BMI is associated with various health implications. For instance, being underweight or obese can increase the risk of certain health conditions, such as malnutrition or cardiovascular diseases.