Body Fat & Composition Calculator

Estimate your body fat percentage and body composition using neck, waist, hip, and height measurements. Track fat-free lean mass, design custom body fat target goals, and estimate daily energy expenditures (TDEE).

Your Physical Profile
yrs
18 yrs100 yrs
cm
100 cm250 cm
kg
30 kg250 kg
cm
25 cm60 cm
cm
50 cm150 cm
Tape Placement Guide
Neck Waist (Navel) Neck Waist (Narrowest) Hips (Widest)
Tape Measure Percentage Fitness
0.0 % Body Fat
--
Body Composition Breakdown
75%
25%
Lean Body Mass
0.0 kg
Muscle, bones, organs & body water. Keep this high!
Fat Body Mass
0.0 kg
Essential fat & stored adipose tissue.
Target Body Fat Goal Planner
%
5%40%
Projected Target Weight --
--
Select a realistic target to compute your target weight.
Caloric & Daily Energy Estimator

Estimated using the lean-mass-based Katch-McArdle Formula, which accounts for body composition.

BMR (Basal Metabolism)
0 kcal

Energy required for basic life functions at rest.

TDEE (Daily Maintenance)
0 kcal

Estimated daily energy usage based on activity.

Fat Loss Target: 0 kcal
Muscle Gain Target: 0 kcal
Unified Health Risk Profile
Low Risk
Waist-to-Height Ratio (WHtR) 0.00
Abdominal Visceral Index Healthy
Your body composition markers indicate a healthy balance. Visceral adiposity risks are low.
Comparative Methodology

Compare results from different body fat formulas using your physical parameters:

Tape Measure Method
0.0%

Circumference based. Best for general fat distribution.

YMCA Formula
0.0%

Waist & body weight based formula.

Deurenberg BMI Method
0.0%

BMI & age regression model.

What is Body Fat Percentage & Why is it Important?

Body fat percentage represents the total mass of fat in your body divided by your total body weight. Unlike body weight or Body Mass Index (BMI), which do not differentiate between muscle tissue, bone density, water retention, and fat deposits, body fat percentage provides a direct measure of body composition. A healthy body composition is a critical marker for metabolic health, insulin sensitivity, cardiovascular endurance, and physical longevity.

The US Navy Circumference Method Explained

This calculator uses the US Navy Circumference Method (often called the Tape Measure Method) to estimate your body fat percentage. It is one of the most thoroughly validated and widely used formulas for estimating body composition without access to specialized clinical equipment like DXA (Dual-Energy X-Ray Absorptiometry) scans, air displacement plethysmography (Bod Pod), or hydrostatic weighing tanks.

The method estimates body density based on anatomical circumferences relative to your height:

  • For Males: The calculation utilizes Neck and Waist circumference measurements.
  • For Females: The calculation utilizes Neck, Waist, and Hip circumference measurements to account for gender-specific fat distribution patterns around the lower body.

Fat Mass vs. Lean Body Mass

Your total body weight is divided into two primary compartments:

  • Fat-Free Lean Body Mass (LBM): This comprises skeletal muscles, bones, internal organs, skin, connective tissues, and body water. Maintaining or increasing your lean body mass through regular resistance and strength training is critical for preserving a healthy resting metabolic rate (BMR).
  • Fat Body Mass: This includes essential fat (fat required for central nervous system function, hormone synthesis, reproductive health, and internal organ cushioning) and storage fat (adipose tissue stored under the skin and around organs). Essential fat is roughly 2% to 5% for men, and 10% to 13% for women.

Estimating Energy Expenditures (BMR & TDEE)

Using your estimated lean body mass, this calculator determines your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE) via the lean-mass-based Katch-McArdle Formula: BMR = 370 + (21.6 * Lean Mass in kg) Since skeletal muscle tissue is highly active metabolically compared to adipose tissue, the Katch-McArdle equation is widely regarded by sports scientists and dietitians as the most accurate estimation tool for individuals tracking their body composition, as it does not overestimate calorie requirements for high-fat weights or underestimate them for high-muscle weights.