Are these calculators really free?

Yes, all our calculators are completely free to use. No registration, no hidden fees, and no limitations on usage.

How accurate are the calculations?

Our calculators use standard mathematical formulas and are tested for accuracy. Results are precise and reliable for most practical applications.

Can I use these on mobile devices?

Absolutely! All our calculators are fully responsive and work perfectly on smartphones, tablets, and desktop computers.

Do you store my calculation data?

No, we don't store any of your input data. All calculations are performed locally in your browser for privacy and security.

Body Fat Calculator - Multiple Calculators

Body Fat Calculator

Estimate your body fat percentage using the US Navy method. Waist, neck, hip (women), height, weight.

Your Measurements

Gender

Units

Weight (kg)

Height (cm)

Waist (cm)

Neck (cm)

Your Results

Body Fat %--

Category--

Uses US Navy method. Measure at natural waist. Results are estimates.

What is a Body Fat Calculator?

A body fat calculator estimates your body fat percentage using body measurements. The US Navy method uses waist, neck, and (for women) hip circumference, along with height and weight, to provide an estimate without calipers or specialised equipment.

The US Navy Formula

For Men

Body Fat % = 495 ÷ (1.0324 - 0.19077 × log10(waist - neck) + 0.15456 × log10(height)) - 450

All measurements in cm.

For Women

Body Fat % = 495 ÷ (1.29579 - 0.35004 × log10(waist + hip - neck) + 0.22100 × log10(height)) - 450

All measurements in cm.

How to Measure

Waist: At navel level, relaxed (not sucked in)
Neck: Below the larynx, relaxed
Hip (women only): At the widest point of the hips

Use a flexible tape measure. Measure in the morning before eating for consistency.

Body Fat Categories

Category	Men	Women
Essential	2-5%	10-13%
Athletes	6-13%	14-20%
Fitness	14-17%	21-24%
Average	18-24%	25-31%
Obese	25%+	32%+

Frequently Asked Questions

How accurate is the Navy method?

It’s an estimate. Accuracy varies ±3-4%. DEXA scans or hydrostatic weighing are more accurate but require equipment.

Do I need to measure in the morning?

Measuring at the same time of day improves consistency. Morning, before eating, is often recommended.

What if my result seems wrong?

Double-check measurements. Ensure you’re measuring at the correct points. The formula assumes average body proportions.