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Fitness
Body Fat Estimator
Estimate body-fat percentage from body circumference measurements.
Updated: May 15, 2026
Input
Estimate body-fat percentage from circumference measurements using a Navy-style formula.
Not a diagnosis or body-composition test. The male formula does not use hip measurement. Measurement site, posture, breathing, and fluid shifts can change the result.
Result
17.9%
Body fat estimate
47 cm
Circumference value
Male
Formula
Use this as a guide and adjust for your real conditions.
Share this tool
How to use
- Enter Sex, Height, Neck, Waist, Hip.
- Check the estimate in the result area.
- Share a reproducible URL if needed.
How to read the result
- Read Body-fat estimate as quick decision-making estimates.
- Do not treat the result as a fixed answer; adjust assumptions to see the range when needed.
Useful tips
- Useful when you want to get a rough body-composition estimate; adjust inputs to compare scenarios.
- Useful when you want to track changes from circumference measurements; adjust inputs to compare scenarios.
- Use results as training guides and adjust for condition, heat, surface, and fatigue.
- If the result feels too demanding, reduce distance, intensity, or duration and recalculate.
Calculation
Uses a circumference-based estimate similar to the U.S. Navy method. Results vary strongly with measurement conditions.
Notes
- Adjust for your condition and environment.
- This is not medical or coaching advice.
- Stop exercising if you feel pain or discomfort.
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FAQ
Are results exact?
Use results as everyday estimates. For exact decisions, confirm with official or specialized sources.
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