Estimate body fat percentage using the US Navy method. Enter height, neck, and waist measurements (plus hips for women) for an accurate result with fitness category interpretation.
Open Body Fat Calculator → free, no sign-inBMI is useful but imprecise — it doesn't distinguish between muscle and fat. Body fat percentage is a more meaningful metric, and the US Navy method for estimating it requires only a few simple measurements: height, neck, and waist (and hips for women). The Body Fat Calculator takes those inputs and gives you an estimated percentage alongside what it means in terms of fitness categories.
Athletes tracking body composition, people monitoring weight loss progress beyond the scale, fitness coaches wanting a quick estimate without calipers or a DEXA scan — this is the practical everyday method.
No tutorials. No learning curve. Open it and get started.
No server uploads. Uses the US Navy formula — the same method used by armed forces worldwide for physical fitness assessments.
Completely free. No trial period. No premium tier for basic functionality. No account required. Use it as often as you need.
One job, done well. Body Fat Calculator was built to solve a specific problem cleanly. No feature bloat, no ads, no distractions.
What is the US Navy method?
It's a formula-based body fat estimation using circumference measurements — widely used for military physical fitness assessments.
How accurate is this method?
Within 3–4% for most people. More accurate than BMI for distinguishing muscle from fat, less accurate than DEXA scanning.
Where should I measure my waist?
At the narrowest point, typically just above the belly button.
What fitness categories are shown?
Essential fat, athletes, fitness, average, and obese — the standard American College of Sports Medicine classifications.
Can I use this for tracking progress?
Yes — consistency in measurement technique matters more than absolute accuracy for tracking changes over time.
Free. Instant. No sign-in. Open it and get the job done.
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