Body Fat % Calculator (U.S. Navy)

Body Fat% Calculator (U.S. Navy) is evaluated from Sex, Height and Waist Circumference. The calculation reports Body Fat%, Fat Mass and Lean Mass.

Results

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About the Body Fat % Calculator (U.S. Navy)

Body Fat% Calculator (U.S. Navy) is treated here as a quantitative relation between Sex, Height, Waist Circumference and Neck Circumference and Body Fat%, Fat Mass, Lean Mass and Body Fat Category.

The calculator uses a multi formula configuration. Each reported value is read as a direct evaluation of the stored rules with the declared field formats and units.

Formula basis:
Men: BF% = 86.010 x log10(Waist - Neck) - 70.041 x log10(Height) + 36.76
Women: BF% = 163.205 x log10(Waist + Hip - Neck) - 97.684 x log10(Height) - 78.387
Fat Mass = Weight x BF% / 100
Lean Mass = Weight - Fat Mass

Interpret the outputs in the order shown by the result fields. Optional inputs affect only the outputs that depend on those variables.

Formula & How It Works

The calculation applies the following relations exactly as recorded in the metadata:

Men: BF% = 86.010 x log10(Waist - Neck) - 70.041 x log10(Height) + 36.76
Women: BF% = 163.205 x log10(Waist + Hip - Neck) - 97.684 x log10(Height) - 78.387
Fat Mass = Weight x BF% / 100
Lean Mass = Weight - Fat Mass

Each output field is produced by substituting the supplied inputs into the relevant relation and then applying the declared rounding or text format.

Worked Examples

Example 1: Average American Male, 35

Inputs

sex: male height_cm: 176 waist_cm: 91 neck_cm: 39 weight_kg: 88
Body Fat%: 27.1%. Fat Mass: 23.8 kg. Lean Mass: 64.2 kg. Body Fat Category: Obese

With Sex = male, Height = 176, Waist Circumference = 91 and Neck Circumference = 39 as the stated inputs, the result is Body Fat% = 27.1%, Fat Mass = 23.8 kg and Lean Mass = 64.2 kg. Each value corresponds to the declared output fields.

Example 2: Athletic Male, 28

Inputs

sex: male height_cm: 182 waist_cm: 79 neck_cm: 40 weight_kg: 82
Body Fat%: 15.3%. Fat Mass: 12.6 kg. Lean Mass: 69.4 kg. Body Fat Category: Fitness

With Sex = male, Height = 182, Waist Circumference = 79 and Neck Circumference = 40 as the stated inputs, the result is Body Fat% = 15.3%, Fat Mass = 12.6 kg and Lean Mass = 69.4 kg. Each value corresponds to the declared output fields.

Example 3: Average American Female, 30

Inputs

sex: female height_cm: 163 waist_cm: 78 neck_cm: 33 hip_cm: 98 weight_kg: 68
Body Fat%: 57.3%. Fat Mass: 38.9 kg. Lean Mass: 29.1 kg. Body Fat Category: Obese

With Sex = female, Height = 163, Waist Circumference = 78 and Neck Circumference = 33 as the stated inputs, the result is Body Fat% = 57.3%, Fat Mass = 38.9 kg and Lean Mass = 29.1 kg. Each value corresponds to the declared output fields.

Example 4: Female Athlete, 25

Inputs

sex: female height_cm: 168 waist_cm: 68 neck_cm: 32 hip_cm: 89 weight_kg: 62
Body Fat%: 46.5%. Fat Mass: 28.8 kg. Lean Mass: 33.2 kg. Body Fat Category: Obese

With Sex = female, Height = 168, Waist Circumference = 68 and Neck Circumference = 32 as the stated inputs, the result is Body Fat% = 46.5%, Fat Mass = 28.8 kg and Lean Mass = 33.2 kg. Each value corresponds to the declared output fields.

Common Use Cases

  • Estimate body fat % without expensive equipment
  • Track fat loss progress over time
  • Check military fitness standards compliance
  • Estimate fat mass and lean mass