Body Fat Calculator

A body fat calculator estimates your body fat percentage from tape measurements, using the US Navy circumference method. It needs your height, neck, and waist — plus hips for women — and gives a percentage with a category. Because it measures shape rather than composition directly, it's an estimate: useful for tracking change over time, less useful as an exact figure. Everything runs on your device.

How to use it

1. Select your sex and enter your height.
2. Measure your neck and waist with a tape measure — plus hips if female — and enter them.
3. See your estimated body fat percentage and category.

Examples

• Male, 175 cm, neck 37 cm, waist 85 cm → about 17.7% (Average).
• Female, 165 cm, neck 33 cm, waist 75 cm, hips 95 cm → about 26.9%.

Frequently asked questions

How accurate is the tape-measure method?

The US Navy method is typically within about 3–4 percentage points of a DEXA scan for most people — good enough to track direction over months, not precise enough to obsess over a single reading. Consistency in how you measure matters more than the absolute number.

Where exactly do I measure waist and neck?

Measure the neck just below the larynx, with the tape sloping slightly downward at the front. Measure the waist horizontally at the navel for men and at the narrowest point for women. Keep the tape snug but not compressing the skin.

What body fat percentage is healthy?

General ranges put men roughly at 14–17% fit and 18–24% average, and women at 21–24% fit and 25–31% average, with athletes below those bands. Essential fat is higher in women for physiological reasons, so the healthy ranges differ by design.

Why do women have higher healthy ranges?

Women carry more essential fat — required for hormone production and reproductive health — typically around 10–13% of body mass versus 2–5% in men. That difference shifts every healthy band upward and is entirely normal.