NavyFit: Body Fat Calculator

NavyFit is a body fat calculator and body fat tracker built on the U.S. Navy formula — the tape measure method used in military body composition assessments worldwide.

Measure your neck, waist and height with a tape measure (plus hips for women) and NavyFit calculates your body fat percentage instantly. No scale, no calipers, no expensive equipment.

✦ WHAT NAVYFIT DOES

• Body fat calculator using the official U.S. Navy formula
• Body fat percentage for men and women
• Metric (cm) and imperial (inch) units
• Illustrated guides showing exactly where to place the tape measure
• Progress chart with your body fat trend over weeks and months
• Calendar with your complete measurement history — edit or add past entries
• Set a body fat goal and watch the gap close
• Weekly reminder when you haven't logged a measurement
• Reference ranges (ACE) showing where your result sits: essential fat, athletic, fitness, average, above average

✦ WHY THE U.S. NAVY METHOD?

The U.S. Navy body fat formula was developed for military body composition testing and is used around the world. It needs nothing but a tape measure and three or four circumference measurements: neck, waist, height, and hips for women.

Results typically land within a few percentage points of a DEXA scan and stay more consistent than consumer bioimpedance scales, whose readings drift with hydration.

Body fat percentage also says more than weight or BMI alone. Two people with the same BMI can have completely different body composition. Tracking body fat percentage over time shows whether you are losing fat — or losing muscle.

✦ MEASURE, TRACK, REPEAT

A single body fat calculation is a snapshot. NavyFit is built for the trend: measure at the same time of day, log it, and let the chart and the calendar do the rest. Your measurement history stays complete and editable, so a forgotten week is never lost.

✦ PRIVACY

Everything stays on your device. No account, no sign-up, no cloud, no data transmission. Your measurements belong to you.