Tool snapshot
Weight minus fat mass
Lean mass helps set protein and strength goals.
Example result
Weight minus fat mass
This is a sample only. Use your own stats and compare the result with your weekly trend.
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Review target
Track trend
lean body mass calculator
Lean Body Mass Calculator
Estimate lean body mass from weight and body-fat percentage.
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How to use this calculator
Start with your current body stats and activity level, then compare the result with a realistic weekly pace. For most weight-loss goals, the number is not meant to be perfect on day one. It is a starting point that becomes more useful after you compare it with two weeks of weight trend data.
What the result means
The key result for this page is Weight minus fat mass. Use it with the live planner to connect the estimate to calories, meals, steps, and a goal date.
Common mistake
Do not cut calories aggressively just because the math says faster is possible. Extreme targets are harder to follow and can reduce training quality, mood, and consistency.
How to adjust
If your 7-day average is not moving after two full weeks, adjust by 100-150 calories or add a small amount of daily walking.
What to track
Track calories, protein, steps, waist measurement, and scale trend. One weigh-in is noisy; the trend is the signal.
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FAQ
Is this lean body mass calculator exact?
It is an estimate based on common formulas. Use it as a starting point and adjust based on real trend data.
What is a safe weight-loss pace?
Many adults use 0.5 to 2 pounds per week, depending on body size, health status, and consistency.
Should I use this instead of medical advice?
No. These calculators are educational tools and do not replace professional medical care.