This is a body fat % calculator based on the US Navy’s formula. It’s very easy to use and seems to be pretty accurate.
After you’ve calculated your body fat %, you can calculate your fat-free mass index (FFMI) using the calculator below. FFMI measures how much muscle you have.
You can look at the FFMI charts on the webpage to see how you compare to the general population. Men and women have different charts. For women, ignore the “FFMI Interpretation” for your number because that is based on men’s charts.
Note that normalized FFMI adjusts FFMI to a height of 180cm (~5’11") so that people with different heights can be compared.
This section applies to women:
The calculator above adjusts women’s FFMI to 5’11" whereas the website below adjusts to 5’4". The normalized FFMI to 5’11" is slightly higher than normalized to 5’4". I’m not sure which one is the right one for women.
The calculator below is the only one I found that adjusts women to 5’4". All other websites (that I’ve seen) adjust both men and women to 5’11".