Body Fat Calculator
Amancalc.com
What is Body Fat Percentage?
Body fat percentage is the proportion of fat tissue in your body compared to your total body weight. Unlike BMI, which only considers height and weight, body fat percentage provides a more accurate assessment of body composition by distinguishing between fat mass and lean mass.
This calculator uses the US Navy body fat formula, which estimates body fat percentage based on measurements of your waist, neck, and (for women) hip circumference, along with your height and weight. This method is widely used and provides a good estimate without requiring expensive equipment.
Advantages of Using Our Body Fat Calculator
- ✓US Navy Formula: Uses the proven US Navy body fat formula, widely recognized for accuracy
- ✓No Special Equipment: Only requires a measuring tape, no expensive body composition devices needed
- ✓Gender-Specific: Different calculations for males and females based on body composition differences
- ✓Dual Unit Support: Works with both metric (kg, cm) and imperial (lbs, inches) units
- ✓Free & Private: No registration required, all calculations are done locally
How to Use the Body Fat Calculator
- 1Select Your Unit SystemChoose between Metric (kilograms and centimeters) or Imperial (pounds and inches) based on your preference.
- 2Enter Your InformationInput your age, gender, weight, and height. Make sure to use accurate measurements.
- 3Measure Your CircumferencesMeasure your waist (at navel level), neck (below the larynx), and (for women) hip (at the widest point). Measure in the morning before eating for best accuracy.
- 4View Your ResultsYour body fat percentage will be calculated automatically and displayed with a category assessment.
Body Fat Categories
For Men:
Minimum necessary for survival
Typical for athletes and very fit individuals
Good fitness level, visible muscle definition
Typical for most men
Higher health risk
For Women:
Minimum necessary for survival
Typical for athletes and very fit individuals
Good fitness level, visible muscle definition
Typical for most women
Higher health risk
Frequently Asked Questions
How accurate is the US Navy body fat formula?
The US Navy formula is reasonably accurate (within 3-5% of DEXA scans) when measurements are taken correctly. However, accuracy depends on proper measurement technique. For the most accurate results, measure in the morning before eating and ensure the tape is level and snug but not compressing the skin.
Why do I need to measure my waist, neck, and hip?
These measurements help estimate body fat distribution. The formula uses the difference between waist and neck (and hip for women) to calculate body fat percentage. This method works because fat distribution patterns correlate with overall body fat percentage.
What's the difference between body fat percentage and BMI?
BMI only considers height and weight, while body fat percentage distinguishes between fat and muscle. A muscular person might have a high BMI but low body fat percentage. Body fat percentage provides a more accurate picture of body composition.
How often should I measure my body fat?
Measure monthly to track changes over time. Daily measurements aren't necessary as body fat changes slowly. For consistency, measure at the same time of day (morning is best) and under similar conditions.
Can I use this if I'm pregnant or have medical conditions?
This calculator is not suitable for pregnant women or individuals with certain medical conditions that affect body composition. If you have concerns about your body fat percentage, consult with a healthcare provider.
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