Body Fat Percentage Calculator
Estimate your body fat percentage using the U.S. Navy circumference method. Select your sex and unit system, then enter your measurements.
Tip: Measure at the same time of day, keep the tape level, and avoid pulling it too tight.
What this calculator tells you
Your body fat percentage is the estimated portion of your body weight that comes from fat mass. Unlike BMI, which only uses height and weight, body fat percentage gives a clearer view of body composition.
This can be useful if you want to:
- Track fat loss while preserving muscle
- Assess fitness progress beyond scale weight
- Set realistic nutrition and training goals
- Monitor long-term health trends
How the body fat percentage is calculated
Method used: U.S. Navy formula
This calculator uses circumference-based equations that estimate body fat from measurements of neck, waist, height, and (for women) hips. It is practical and widely used for field estimates.
- Men: uses neck, waist, and height
- Women: uses neck, waist, hip, and height
The calculator automatically converts metric values (cm) to inches when needed so formula outputs remain accurate.
Measurement guide for better accuracy
- Height: Stand tall without shoes.
- Neck: Measure just below the larynx (Adam’s apple), tape horizontal.
- Waist: Measure at the narrowest point of the torso or around navel level if needed.
- Hips (women): Measure at the widest point of the hips/glutes.
Understanding your result
After calculation, your result is shown with a category label. These categories are common reference ranges and can vary by source, age, and athletic background.
Typical body fat categories
- Men: Essential (2–5%), Athletes (6–13%), Fitness (14–17%), Average (18–24%), Obesity (25%+)
- Women: Essential (10–13%), Athletes (14–20%), Fitness (21–24%), Average (25–31%), Obesity (32%+)
Important: This tool provides an estimate, not a medical diagnosis. For clinical assessment, use methods like DEXA scans, hydrostatic weighing, or professional skinfold testing.
How to lower body fat percentage safely
1) Build a sustainable calorie deficit
Fat loss requires a consistent but moderate energy deficit. Avoid crash dieting, which can reduce muscle mass and increase fatigue.
2) Prioritize protein and resistance training
Strength training and adequate protein help preserve lean mass while losing fat. This improves body composition and keeps metabolism more stable.
3) Focus on sleep and stress management
Poor sleep and high stress can increase cravings and interfere with recovery. Aim for consistent sleep quality and daily stress-control habits.
4) Track trends, not day-to-day noise
Body composition changes slowly. Measure every 2–4 weeks under similar conditions to see meaningful trends.
Frequently asked questions
Is body fat percentage better than BMI?
For many people, yes. BMI is useful at a population level, but body fat percentage is usually more informative for individual fitness tracking.
How often should I measure?
Every two to four weeks is usually enough. Daily measurements can create unnecessary noise due to hydration and normal fluctuations.
Can this calculator be wrong?
Yes, all field formulas have error margins. Measurement technique, body shape, and tape placement can affect estimates. Still, when done consistently, this method is very useful for progress tracking.