Body Fat Calculator
Fill in the values and the answer updates as you type.
How the Body Fat Calculator works
U.S. Navy formula based on height, neck, waist, and (for women) hip measurements. It is an estimate.
Inputs and results
The Body Fat Calculator takes 6 inputs and gives 3 results.
What you enter
- Sex — starts at male. Choose from: male and female.
- Weight (kg) — starts at 75.
- Height (cm) — starts at 175.
- Neck (cm) — starts at 38.
- Waist (cm) — starts at 85.
- Hip (women) (cm) — starts at 95.
What you get
- Body fat
- Fat mass (kg)
- Lean mass (kg)
Example: Body Fat Calculator with the starting values
With sex male, weight 75 kg, height 175 cm, neck 38 cm and waist 85 cm, the calculator returns:
| Body fat | 16.94% |
|---|---|
| Fat mass (kg) | 12.7 |
| Lean mass (kg) | 62.3 |
Change any value above and the results update straight away.
Body Fat Calculator FAQ
How do I use the Body Fat Calculator?
Enter sex, weight, height and neck in the fields, then read body fat, fat mass (kg) and lean mass (kg) in the result panel. The answer updates as you type, and you can press Calculate or Enter to refresh it. Use “Copy link” to share your exact numbers with someone else.
What does the Body Fat Calculator calculate?
Body fat percentage using the U.S. Navy method. It returns body fat, fat mass (kg) and lean mass (kg) from the 6 values you provide.
What values does the Body Fat Calculator start with?
It opens with sex male, weight 75 kg, height 175 cm and neck 38 cm so you can see a working result straight away. Replace them with your own numbers, or press Reset to return to these starting values.
Is the Body Fat Calculator free and private?
Yes. It is free, needs no account, and runs in your browser, so nothing you type is sent to or stored on our servers. See the Privacy Policy for details.
Can I rely on the Body Fat Calculator for medical or health decisions?
Treat the result as a well-rounded estimate. Real situations often have details a general calculator cannot know, so confirm medical or health decisions with a qualified professional. See the Disclaimer for more.