The Body Fat Calculator helps you estimate your body fat percentage using basic body measurements. This tool supports both US customary units and metric units, making it easy to use worldwide. Based on the U.S. Navy method and the BMI method, the calculator offers a reliable estimate of your total body fat, lean mass, and ideal fat levels for your age and gender.

To get the most accurate results, measure your waist, neck, and (for women) hip size to the nearest 0.5 cm or 1/4 inch. This calculator is especially useful if you’re monitoring fat loss or tracking fitness goals.

Body Fat Calculator Results Explained

After entering your data (gender, age, weight, height, neck, waist), the Body Fat Calculator returns:

• Body Fat % (U.S. Navy Method): e.g., 15.7%
• Body Fat Category: e.g., Fitness
• Body Fat Mass: e.g., 11.0 kg
• Lean Body Mass: e.g., 59.0 kg
• Ideal Body Fat % (Jackson & Pollock): e.g., 10.5%
• Fat to Lose to Reach Ideal: e.g., 3.6 kg
• BMI-based Body Fat %: e.g., 16.1%

What Is Body Fat?

Body fat refers to adipose tissue, which stores energy and helps regulate hormones, protect organs, and insulate the body. It includes:

• Essential fat: Vital for survival (2–5% in men, 10–13% in women).
• Storage fat: Found under the skin and around organs.

Too much storage fat leads to overweight or obesity, but having too little fat can also cause health issues, especially hormonal imbalances and reduced organ protection.

Healthy Body Fat Ranges

By Gender:

By Age (Ideal Fat % – Jackson & Pollock):

The Dangers of Excess Body Fat

High levels of visceral fat (fat around organs) increase the risk of:

• Heart disease
• Type 2 diabetes
• High blood pressure
• Stroke
• Sleep apnea
• Certain cancers

According to the World Health Organization, obesity is a major cause of preventable death globally. In the U.S. alone, it contributes to over 100,000 deaths annually.

Visceral fat also disrupts hormone balance, increases LDL (bad cholesterol), and reduces HDL (good cholesterol). It raises insulin resistance, a key factor in diabetes.

How the Body Fat Calculator Works

U.S. Navy Method

This method uses body measurements:

• Men: Neck and waist circumference.
• Women: Neck, waist, and hip circumference.

U.S. Navy Formula (Metric):

• Men:
  BFP = 495 / (1.0324 - 0.19077 × log10(waist - neck) + 0.15456 × log10(height)) - 450
• Women:
  BFP = 495 / (1.29579 - 0.35004 × log10(waist + hip - neck) + 0.22100 × log10(height)) - 450

These estimates assume average body types. For greater precision, use tools like bioelectric impedance or hydrostatic weighing.

Alternate Method: BMI-Based Body Fat Calculation

This method uses your Body Mass Index (BMI), age, and gender:

• Men (Adults):
  BFP = 1.20 × BMI + 0.23 × Age – 16.2
• Women (Adults):
  BFP = 1.20 × BMI + 0.23 × Age – 5.4
• Boys:
  BFP = 1.51 × BMI – 0.70 × Age – 2.2
• Girls:
  BFP = 1.51 × BMI – 0.70 × Age + 1.4

Use the BMI Calculator to get your BMI before using this method.

Fat Mass and Lean Mass Calculation

• Fat Mass (FM) = Body Fat % × Weight
• Lean Mass (LM) = Weight – Fat Mass

These values help assess progress in weight loss or fitness training programs.

Final Thoughts

Monitoring your body fat percentage is more important than tracking weight alone. Whether your goal is fat loss, muscle gain, or improving your overall health, using a Body Fat Calculator regularly can help you stay on track. Understanding your current fat level, your ideal fat percentage, and how to improve it is the first step toward a healthier body and mind.

Related Tools

• BMI Calculator
• Calorie Calculator
• Ideal Weight Calculator

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Estimate your body fat percentage using our Body Fat Calculator. Get insights using U.S. Navy and BMI methods. Fast, accurate & free.

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