Body Fat (US Navy), Lean Body Mass & Body Surface Area Calculator

Compute US Navy Body Fat %, fat-free Lean Body Mass (kg), Mosteller BSA (m²), and Waist-to-Hip Ratio.

Estimated Body Fat Percentage (US Navy Method)
16%
Lean Body Mass: 63 kg • Fat Mass: 12 kg • BSA: 1.91 m²
Lean Body Mass (Navy / Boer) 63 kg / 58.3 kg
Adipose Fat Mass 12 kg
Body Surface Area (Mosteller) 1.91 m²
Waist-to-Hip Ratio (WHR) 0.88
Inputs
⚡ Scenarios:
Select appropriate anthropometric regression formula.
kg
Total body mass in kilograms.
cm
Height in centimeters.
cm
Measured horizontally at navel (men) or narrowest abdominal point (women).
cm
Measured just below the larynx.
cm
Largest horizontal gluteal circumference (used in female Navy equation & WHR).
Results & Graph
Estimated Body Fat Percentage (US Navy Method)
16%
Lean Body Mass: 63 kg • Fat Mass: 12 kg • BSA: 1.91 m²
Lean Body Mass (Navy / Boer)
63 kg / 58.3 kg
Adipose Fat Mass
12 kg
Body Surface Area (Mosteller)
1.91 m²
Waist-to-Hip Ratio (WHR)
0.88

Body Mass Composition (kg)

Fat-Free Lean Body Mass vs. Adipose Tissue Mass
Graph 1 • US Navy Body Fat Classification Spectrum Hodgdon-Beckett circumference regression
Essential / Athlete 4 Fitness 14 Acceptable 18 Elevated Adiposity 25 42 16 %
Graph 2 • Fat-Free Lean Body Mass vs. Adipose Fat Mass Skeletal muscle, bone, organs, and total body water vs. fat
BODY WEIGHT 75 kg Fat-Free Lean Mass (63.0 kg) 63 (84.0%) Adipose Fat Tissue (12.0 kg) 12 (16.0%)
Graph 3 • Waist-to-Hip Ratio (WHR) Central Adiposity Scale WHO visceral cardiometabolic risk screening cutoffs
Low Risk (<0.90) 0.65 Moderate (0.90–0.99) 0.9 High Central Risk (≥1.00) 1 1.15 0.88 WHR
Summary: Body weight of 75 kg consists of 63 kg lean mass and 12 kg fat mass (16%).
Summary: Using the US Navy Hodgdon-Beckett circumference formula for a 176 cm, 75 kg male, estimated body fat is 16% (12 kg fat mass and 63 kg fat-free lean mass; Boer formula LBM = 58.3 kg). Mosteller Body Surface Area is 1.91 m² and Waist-to-Hip Ratio is 0.88.
⚠️ Clinical Anthropometry Note: Circumference-based body fat formulas have a standard error of ±3%–4% compared to DEXA scans. Use consistent tape placement at the navel/iliac crest and below the larynx.
⚡ Send result to: BMI →Calorie & TDEE →Pace, 1RM & HR Zones →
Interactive chart & math engine powered by CalculatorGraph

Formula & Mathematical Methodology: Hodgdon-Beckett US Navy Body Fat, Boer LBM & Mosteller BSA Equations

Body Fat %male = 4951.0324 − 0.19077 log10(Waist − Neck) + 0.15456 log10(Height) − 450
BSA = Height (cm) × Weight (kg)3600
Male BF% = 495 / [1.0324 − 0.19077 log10(Waist−Neck) + 0.15456 log10(Height)] − 450; BSA = √[(Height_cm × Weight_kg) / 3600]
  • Waist, Neck, Hip, Height: Circumferences and height in centimeters
  • BSA: Body Surface Area in square meters (Mosteller 1987)

Rounding: Rounded to 1–2 decimal places.

Worked Example: Male: 75 kg, 176 cm Height, 84 cm Waist, 38 cm Neck

Estimate body fat percentage, lean mass, and BSA.

  1. Waist − Neck = 46 cm → log10(46) = 1.66276; log10(176) = 2.24551.
  2. Body Fat % = 495 ÷ (1.0324 − 0.3172 + 0.3471) − 450 = 15.9%.
  3. Fat mass = 12.0 kg; Lean Body Mass = 63.0 kg; Mosteller BSA = 1.91 m².
Result: 15.9% Body Fat (63.0 kg lean mass, 12.0 kg fat mass) and 1.91 m² BSA.

Frequently Asked Questions

Why is Body Surface Area (BSA) used in medicine?

Mosteller BSA (in m²) is used in physiology and clinical pharmacology to normalize cardiac index, glomerular filtration rate, and specialized medication dosing.

Health & Fitness · Anthropometry & Body Composition

Body Fat (US Navy), Lean Body Mass & Body Surface Area Calculator: inputs, method, and how to read the result

Compute US Navy Body Fat %, fat-free Lean Body Mass (kg), Mosteller BSA (m²), and Waist-to-Hip Ratio.

Choose inputs for the case you are checking

The defaults are illustrative. Replace them with values for your case and keep the units shown beside each field.

  • Biological Sex Equation: Select appropriate anthropometric regression formula.
  • Body Weight: Total body mass in kilograms.
  • Standing Height: Height in centimeters.
  • Waist Circumference: Measured horizontally at navel (men) or narrowest abdominal point (women).

What the calculation includes

With the default values shown, Estimated Body Fat Percentage (US Navy Method) is 16%. The calculation follows Hodgdon-Beckett US Navy Body Fat, Boer LBM & Mosteller BSA Equations; the formula and variable definitions above show how the inputs combine.

One-input check: With the other defaults held constant, changing Biological Sex Equation from Male (Waist, Neck & Height Equation) to Female (Waist, Hip, Neck & Height Equation) changes Estimated Body Fat Percentage (US Navy Method) from 16% to 26.6%. This is a comparison inside the calculator's stated model, not a prediction.

Where to use caution

  • Tape measurements are taken against bare skin without compressing soft tissue.
  • Circumference equations have a ±3%–4% margin of error relative to DEXA.

Scope: Global Clinical & Fitness Reference Check the assumptions and limitations against your situation before relying on the estimate.

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