Work out bone mass estimate instantly with clear inputs, formula shown and shareable results.
Bone mineral mass is roughly 4.3% of body weight in men and 3.8% in women, so a 75 kg man carries about 3.2 kg. The figure varies by 15% either way with frame size and mineral density, and it changes very slowly - which is why bioimpedance scales report bone mass that barely moves between weigh-ins.
Bone mass estimate
bone = body weight x 0.043 (men) or 0.038 (women)
Typical variation
plus or minus about 15% with frame size and density
These figures are population-average estimates, not a medical assessment or diagnosis. Body composition equations carry errors of several percentage points, and healthy ranges vary with age, ethnicity, muscularity and medical history. Discuss weight or body composition goals with a qualified clinician or dietitian.
Because bone mass genuinely changes over years, not weeks, and most scales derive it from a fixed fraction of your weight anyway.
By DEXA scanning, which reports areal density in g/cm2 and a T-score against young adult norms. Mass alone does not diagnose osteoporosis.