Health & Fitness Calculators
Lean Body Mass
Estimate your lean body mass and body composition.
Enter your details to see your body composition results.
Transparency note
Accuracy and limitations
Calzivo tools are built for practical estimates, conversions, and checks. Some tools use standard formulas or simplified assumptions, and results can be affected by input accuracy, rounding, units, local rules, or changing official requirements.
Health and fitness results are estimates, not medical advice. Formulas simplify real bodies and cycles, so important health decisions should be checked with a qualified clinician.
How to Use This Tool
Use these steps to enter the right inputs and interpret the result correctly.
Choose gender and unit system.
Enter weight and height in the selected units.
Press Calculate Lean Body Mass to estimate lean mass, fat mass, and body fat percentage.
Use the result as a formula estimate, not a body-composition diagnosis.
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Macro Calculator
Estimate daily protein, carbs, fat, calories, and macro split targets from body stats, goals, and activity.
Body Fat Calculator
Estimate body fat percentage with Navy circumference or BMI-based methods, reference ranges, and neutral context.
Ideal Weight Calculator
Compare common ideal-weight formulas with a healthy BMI range and clear estimate limitations.
Related Guides
Background reading and explanations related to Lean Body Mass.
BMI Limits: What BMI Can and Cannot Tell You
Understand BMI as a screening estimate and where body composition context matters.
BMI Explained (What It Means and When It Misleads You)
What your BMI score really means.
Ideal Weight Is an Estimate, Not a Diagnosis
Read ideal-weight formula results as rough context, not medical conclusions.
Frequently Asked Questions
Common questions about Lean Body Mass and how to read the result.
What is lean body mass?
Lean body mass is the estimated body weight that is not fat, including muscle, bone, organs, water, and other non-fat tissue.
Which formula does this use?
This calculator uses the Boer formula, which estimates lean body mass from height, weight, and gender.
Is lean body mass the same as muscle mass?
No. Lean body mass includes muscle, but it also includes bone, organs, water, and other non-fat tissue.
How accurate is this estimate?
It is a rough formula estimate. It can be less accurate for athletes, pregnancy, older adults, or unusual body composition.
Can this diagnose body fat percentage?
No. It should not be used to diagnose, treat, or manage a medical condition. More direct body-composition methods may be needed.
Who should use professional guidance?
People under 18, pregnant people, older adults, athletes, and anyone with a medical condition should use professional guidance.