💪 BMI vs Body Fat Percentage — US Navy Formula
Understand the difference between BMI and body fat percentage and which is more accurate. Uses the medically-validated US Navy logarithm formula (1–3% accuracy vs DEXA scan). Also shows BMI, Lean Body Mass (LBM), and BMR.
Body Fat Classification (Men)
Body Fat Calculator
Frequently Asked Questions
Is body fat percentage more accurate than BMI?
BMI is a simple ratio of weight to height and doesn't distinguish between fat and muscle. Body fat percentage is more accurate because two people with the same BMI can have very different amounts of fat. However, BMI is still useful as a quick screening tool.
What measurements do I need?
Men need 3 measurements: height, neck circumference (below the larynx), and waist circumference (at navel level). Measure in centimeters or inches consistently.
What is Lean Body Mass (LBM)?
LBM is your total body weight minus fat mass: LBM = Weight × (1 − body fat%). It includes muscles, bones, organs, and water. Tracking LBM is more meaningful than scale weight — an increase in LBM indicates muscle gain even if total weight stays the same.