Body Fat Calculator
Use this body fat calculator to estimate body fat percentage from height, neck, waist, and hip measurements. It is more body-composition aware than BMI, but still depends heavily on accurate measuring.
Uses the US Navy circumference method. Measurement accuracy matters.
How it's calculated
Body fat estimate = US Navy circumference formula
The US Navy method uses different circumference equations for men and women. Men use height, neck, and waist; women use height, neck, waist, and hips.
What your result means
| Category | Range | What it means |
|---|---|---|
| Essential fat | Very low | Needed for basic physiology; not a realistic general fitness target. |
| Fitness range | Lower-middle | Often seen in active people with consistent training and nutrition. |
| Average range | Middle | Common for many adults and best interpreted alongside waist and health markers. |
| Higher range | Upper | May indicate higher health risk, especially with a larger waist circumference. |
Why body fat percentage matters
Body fat percentage separates body composition from scale weight. Two people can share the same BMI while having very different muscle and fat levels.
How to measure correctly
Measure on bare skin, keep the tape level, and avoid pulling it tight. Small measurement errors can noticeably change the result.
Body fat vs BMI
BMI is faster and works well for broad screening. Body fat percentage is more specific, but home estimates are still approximations.
Frequently asked questions
Is the body fat calculator accurate?
It is an estimate. The US Navy method is useful for tracking trends, but professional methods like DEXA are more precise.
Where do I measure my waist?
Measure around the abdomen at about navel level, keeping the tape level and snug but not compressed.
Why do women need hip measurement?
The Navy formula for women uses hip circumference because fat distribution differs by sex.
Is body fat percentage better than BMI?
It can be more informative because it estimates composition, but it is still only one signal and depends on measurement quality.