Current reference20%Average range
Six range references
One number. Many bodies.
These anonymous generated figures show ranges—not diagnoses or promises. Muscle, height, age, posture, sex characteristics, and fat distribution all change appearance at the same estimate.
What is measured
Tape landmarks, not pixels.
The calculator uses legacy Navy-style circumference equations. No body photo is analyzed or uploaded.
Male height · neck · waistFemale height · neck · waist · hipsOutput estimate + visual range
NeckWaistHips
Tape level. Body relaxed.Measure after a normal exhale without compressing skin.
Open formulas and methodology
Male equation
86.010 log₁₀(waist − neck) − 70.041 log₁₀(height) + 36.76Female equation163.205 log₁₀(waist + hips − neck) − 97.684 log₁₀(height) − 78.387Inputs are converted to inches before the logarithms are applied. This is a consumer circumference estimate, not the current official U.S. Navy BCA process. We cross-checked coefficients and landmarks against the official service instruction.
Repeatability protocol
Consistency beats another decimal place
- 01Same timeSimilar hydration and training state
- 02Same landmarksTape level at neck, waist, and hips
- 03Normal exhaleNo bracing or forced emptying
- 04Repeat twiceAverage the closest two readings
- 05Compare weeksDaily change is mostly noise
Interpretation boundary
An estimate is not a diagnosis
When not to rely on this result
A circumference estimate cannot measure tissue directly or identify fat around organs. Muscle also changes neck, torso, and hip size, while a tape moved one or two centimeters can shift the output. If the number will guide medical care, eating-disorder treatment, competition preparation, or another major health decision, speak with a qualified professional.
For fictional visual editing rather than measurement, use the clearly labeled AI Body Editor and never present its output as a health result.