Body Fat Calculator

Metric (cm, kg) US (in, lbs)

Age

Gender

Height (in)

Weight (lbs)

Neck (in)

Waist (in)

Body Fat Calculator – Body Fat Percentage Explained

Use this free Body Fat Calculator to estimate your body fat percentage using the U.S. Navy and BMI methods. Enter your measurements in metric or US units and get instant results, including your body fat category, fat mass, lean mass, and ideal body fat for your age and gender.

Body Fat Percentage Formulas

U.S. Navy Method (Metric):
Male: BFP = 495 / (1.0324 - 0.19077 × log10(waist - neck) + 0.15456 × log10(height)) - 450
Female: BFP = 495 / (1.29579 - 0.35004 × log10(waist + hip - neck) + 0.22100 × log10(height)) - 450
U.S. Navy Method (US):
Male: BFP = 86.010 × log10(waist - neck) - 70.041 × log10(height) + 36.76
Female: BFP = 163.205 × log10(waist + hip - neck) - 97.684 × log10(height) - 78.387
BMI Method:
Male: BFP = 1.20 × BMI + 0.23 × Age - 16.2
Female: BFP = 1.20 × BMI + 0.23 × Age - 5.4

Body Fat Category Table (ACE)

Description	Women (%)	Men (%)
Essential fat	10–13	2–5
Athletes	14–20	6–13
Fitness	21–24	14–17
Average	25–31	18–24
Obese	32+	25+

Jackson & Pollock Ideal Body Fat Percentages

Age	Women (%)	Men (%)
20	17.7	8.5
25	18.4	10.5
30	19.3	12.7
35	21.5	13.7
40	22.2	15.3
45	22.9	16.4
50	25.2	18.9
55	26.3	20.9

Example Calculation

A 30-year-old male, 5'7" (67 in), 143 lbs, neck 15 in, waist 32 in:
BFP = 86.010 × log10(32 - 15) - 70.041 × log10(67) + 36.76 ≈ 17.0%
Fat mass = 143 × 0.17 = 24.3 lbs
Lean mass = 143 - 24.3 = 118.7 lbs

What is Body Fat?

Body fat is the total mass of fat divided by total body mass. It includes essential fat (necessary for life and reproductive functions) and storage fat (accumulated in adipose tissue). Healthy body fat ranges differ by gender and age. Excess body fat can increase the risk of health problems, while too little can also be harmful.