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Body fat calculator

Estimate body fat percentage with the US Navy formula using body measurements.

When to use

Quick guide on when this calculator is most useful and when to recalculate your values.

  • •If you want a body composition estimate without calipers or bioimpedance.
  • •If you track waist size and fat loss together with scale weight.
  • •If you compare visual progress with body measurements.
  • •If you want a simple lean-mass estimate for other calculators.
What result meansTipsFAQ

Enter parameters

System
Sex

Body fat percentage

16.9%
Body fat percentage
Fit range
Category

US Navy formula

Uses height, waist, neck, and hips for women.

What it means

4

A quick overview of how the result is formed and how to apply it in practice.

The US Navy formula estimates body fat from body measurements.
It is a practical home method for tracking body composition without lab testing.
Accuracy depends heavily on measurement quality, especially waist and neck.
It is more useful for trend tracking than as an absolute one-day truth.

Tips

5

Small practical steps to help you apply the result day to day.

Measure waist and neck at the same points every time.
Do not suck in your stomach or pull the tape too tight.
For women, measure hips at the widest point.
Compare the result every 2-4 weeks, not every day.
Use this together with body weight and progress photos.

FAQ

4

Short answers to common questions about calculations and interpretation.

How accurate is the US Navy formula?

It is an estimate. It is practical for home use, but accuracy depends on correct measurements.

Why is neck measurement included?

Neck circumference is part of the formula and helps adjust the body fat estimate.

Why do women need hips but men do not?

The women's formula accounts for a different fat distribution pattern, so hips are included.

What is more useful: body fat or BMI?

Body fat usually reflects body composition better, while BMI is useful as a broad starting reference. They work well together.

This is an estimate and does not replace professional body composition testing.

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