Body Fat Calculator
Estimate your body fat percentage using circumference measurements or BMI. See your fat mass, lean mass, and how you compare to standard categories.
Biological sex for calculation
Your current age
Measure at navel level
Measure below Adam's apple
📊 Body Fat Categories
Why Body Fat Matters
Body fat percentage is a better indicator of health and fitness than weight alone. Two people at the same weight can have very different body compositions. Tracking body fat helps you understand whether you're losing fat or muscle during weight loss.
How to Measure
- Use a flexible tape measure
- Measure first thing in the morning
- Stand relaxed, don't flex or suck in
- Keep tape snug but not tight
- Take 2-3 measurements, use average
Frequently Asked Questions
The US Navy method is accurate within ±3-4% for most people when measurements are taken correctly. The BMI-based method is less accurate (±5-7%) and tends to overestimate body fat in athletic individuals. For clinical accuracy, consider DEXA scans or hydrostatic weighing.
Stand relaxed and measure at your navel level (belly button), not at your belt line or narrowest point. Keep the tape snug but not compressing the skin. Measure after exhaling normally, not while sucking in your stomach.
Measure just below your Adam's apple (larynx), keeping the tape level around your neck. Don't flex your neck muscles. The tape should be snug but allow you to slip a finger underneath.
Women naturally store more fat in the hip and thigh area. The Navy formula accounts for this difference in fat distribution patterns between sexes by including hip circumference for women.
Essential fat is necessary for normal body functions and is stored in organs, bone marrow, and the nervous system. Men need ~3% and women ~12% essential fat. Storage fat accumulates under the skin and around organs, and is the fat you can lose.
No. Extremely low body fat (below essential levels) is dangerous and can cause hormonal problems, weakened immunity, and organ damage. Athletes may safely maintain lower levels during competition, but this isn't sustainable or healthy long-term.
Different calculators use different formulas (Navy, Jackson-Pollock, YMCA). Each has different accuracy levels and may give varying results. For tracking progress, consistency matters more than absolute accuracy—use the same method each time.
Monthly is ideal for tracking progress. Body fat changes slowly—daily or weekly measurements will mostly show normal fluctuations from hydration, food intake, and measurement variance. Measure at the same time of day under similar conditions.
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Important Note
This calculator provides estimates based on mathematical formulas. For accurate body fat measurement, consider professional methods like DEXA scans, hydrostatic weighing, or skinfold calipers administered by trained professionals. Consult a healthcare provider before making significant changes to your diet or exercise routine.