BMI & Body Metrics Calculator

Calculate adult BMI, a reference weight range, and optional fat-free mass and FFMI with transparent limitations and South Asian context.

Adult BMI with body-composition context

Calculate BMI from height and weight, review a reference weight range, and optionally add body fat to estimate fat-free mass and FFMI. South Asian risk context and the limits of BMI are shown beside the result.

How to use the BMI calculator

  1. Enter adult age, height and weight in metric or imperial units.
  2. Optionally add a measured body-fat percentage for fat-free mass and FFMI context.
  3. Review BMI as one screening measure, then carry the same profile into BMR or TDEE.

What BMI can and cannot show

BMI does not distinguish fat, muscle, bone structure or fat distribution. Adult categories are screening references; athletes, pregnant people, people under 20 and anyone making a medical decision need more appropriate assessment.