Estimate body fat from measurements.
This uses the U.S. Navy method and supports either inches or centimeters.
Nutrition & Weight Loss
Body Fat Calculator
Use this body fat calculator to estimate body fat percentage from body measurements using the U.S. Navy method.
How it works
How to use the body fat calculator
Body Fat Calculator is built to help you estimate body composition from measurements when scale weight alone is not telling the full story. It works best for people who want a practical body fat checkpoint without using a lab or scan. Instead of guessing, you can use the result as a cleaner starting point and then adjust based on what happens in real life over the next few days or weeks.
To use this calculator well, measure the required body parts consistently and use the same unit each time. Once you have the body fat estimate, compare it to your current routine, training demands, and recovery. The best number on paper is still the number you can follow consistently enough to learn from.
measurement error, tape placement, posture, and hydration can all shift the estimate. That does not make the tool useless. It just means the output should guide your next decision instead of replacing judgment. Track the trend over time rather than obsessing over a single reading, especially when the measurements are self-reported.
FAQ
Common questions about this calculator.
Use these quick answers as a starting point, then compare the result to your real-world progress.
What does the body fat calculator tell me?
It gives you a practical estimate that can help you make a better starting decision. You can use it to reduce guessing, then refine the plan after you track your response over time.
How accurate is the body fat calculator?
measurement error, tape placement, posture, and hydration can all shift the estimate The result is most useful when you treat it as an estimate, track the outcome, and adjust based on real-world feedback.
What should I do after I get my result?
Track the trend over time rather than obsessing over a single reading, especially when the measurements are self-reported. When progress is not matching the estimate, make one small adjustment at a time so you can see what actually changed.
Who is this calculator best for?
This calculator is best for people who want a practical body fat checkpoint without using a lab or scan. It is written for regular users first, but it can still be useful for athletes who want a simple starting point before getting more detailed.
When should I recalculate?
Recalculate when one of the main inputs changes in a meaningful way, like bodyweight, training volume, pace, calories, or your goal. You can also rerun it when your progress stalls and you want a fresh checkpoint.
These estimates are for educational purposes only and are not medical advice.
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