Body Mass Index (BMI) Calculator

This calculator computes the Body Mass Index (BMI) — a person's weight in kilograms divided by the square of their height in metres. It is used as a measure to estimate body-fat levels and to group weights into categories that are associated with certain obesity-related health problems.

Warning: BMI is not a substitute for a thorough medical examination of body fat and related conditions, and should not be relied on for that purpose.

A BMI calculator is an easy way to gauge a healthy weight versus obesity, since people with obesity are more prone to many chronic diseases, such as:

• Type 2 diabetes
• Heart disease
• Cancer
• A higher likelihood of premature death

When someone learns their BMI is high, following a healthy diet and exercising can help bring it back toward the normal range.

Is the BMI calculator right for everyone?

For most adults, BMI is a good estimate of weight-related risk — but in some cases the values may be inaccurate, such as for:

• Children, whose BMI is calculated differently based on age, weight and height.
• Pregnant and breastfeeding women.
• Very muscular people, since BMI may read excess muscle as fat even though they're healthy.
• Some ethnic backgrounds, where risk thresholds can differ.
• Older adults (60+), as muscle mass falls and body fat rises with age.