Lean Body Mass Calculator
Estimate your lean body mass using your height, weight, and the Boer formula — separate from fat mass.
Calculated instantly in your browser — nothing is sent to or stored on our servers.
How This Is Calculated
Lean body mass (LBM) is your total body weight minus body fat — muscle, bone, organs, and water. It’s a useful baseline for tracking strength and metabolic changes over time.
The Formula
Men: LBM = 0.407 × weight(kg) + 0.267 × height(cm) − 19.2. Women: LBM = 0.252 × weight(kg) + 0.473 × height(cm) − 48.3.
Why It Matters
Two people can weigh the same yet have very different body composition. Tracking lean mass alongside weight shows whether changes come from muscle or fat — this is a formula-based estimate, and DEXA scans or BIA scales are more precise.
Estimates work best as a trend, not a single number.
Boer formula estimates can vary from direct measurement methods. Use it to track relative change over weeks, not as a precise clinical value.
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