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Try our free Body Fat Calculator for instant results.
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Body fat percentage is more informative than weight alone because it distinguishes fat from muscle and bone.
The Formula
BF% = 495 ÷ (1.0324 − 0.19077×log(waist−neck) + 0.15456×log(height)) − 450
Standard formula used by professionals worldwide
Worked Example
Step-by-step
Neck 38, waist 90, height 178 → BF% ≈ 20% → Fitness category
Key Concepts
- Accuracy: Results are as accurate as the inputs you provide
- Units: Always use consistent units throughout your calculation
- Verification: Double-check important calculations before making decisions
- Professional advice: For major financial, health, or structural decisions, consult a qualified professional
Privacy and Security
- All calculations run entirely in your browser
- No data is sent to any server
- No sign-up or personal information required
- Your data stays private — always
Frequently Asked Questions
What is visceral fat?
Fat stored around organs. More dangerous than subcutaneous fat. Reduced primarily by exercise.
How to lower body fat without losing muscle?
Moderate calorie deficit, high protein intake, resistance training.
Is lower always better?
No — essential fat is necessary for hormonal function. Too low is as problematic as too high.