Body Fat Mass (BFM) Calculator
Calculate your total fat weight and lean body mass accurately.
What is Body Fat Mass (BFM)?
Body Fat Mass (BFM) represents the actual weight of fat within your body. While Body Fat Percentage (BFP) tells you the ratio of fat to total weight, the BFM gives you a concrete number in kilograms or pounds. This metric is essential for athletes and individuals on weight loss journeys to distinguish between losing fat and losing muscle.
The BFM Calculation Formula
To calculate your Body Fat Mass, you need your total body weight and your body fat percentage. The formula is straightforward:
BFM = Total Body Weight × (Body Fat Percentage / 100)
Once you know your BFM, you can calculate your Lean Body Mass (LBM) by subtracting the fat weight from your total weight:
LBM = Total Body Weight – Body Fat Mass
Example Calculation
If an individual weighs 200 lbs and has a body fat percentage of 25%:
- Body Fat Mass: 200 × 0.25 = 50 lbs of pure fat.
- Lean Body Mass: 200 – 50 = 150 lbs (bones, muscles, water, organs).
Standard Body Fat Categories
| Category | Men (%) | Women (%) |
|---|---|---|
| Essential Fat | 2-5% | 10-13% |
| Athletes | 6-13% | 14-20% |
| Fitness | 14-17% | 21-24% |
| Average | 18-24% | 25-31% |
| Obese | 25%+ | 32%+ |
Why Monitoring BFM is Important
Tracking BFM is often more useful than tracking total weight alone. For example, if you start weightlifting, your total weight might stay the same, but your BFM might decrease while your Lean Body Mass increases. Using a BFM calculator helps ensure that your diet and exercise program are resulting in fat loss rather than muscle wastage.