This one is a bit tricky, so I'll try to explain a bit how it works.
Unlike a straight forward web form, where you plug the numbers and get a result, ours is a progressive chart, and uses your historical information.
The formula currently (we'll add a few optional formulas) used is the US Navy formula:
http://www.nhrc.navy.mil/programs/BodyFat/index.html
For men:
%Fat=495/(1.0324-.19077(log(abdomen-neck))+.15456(log(height)))-450
For women:
%Fat=495/(1.29579-.35004(log(abdomen+hip-neck))+.22100(log(height)))-450
But as you progress in your fat loss, your dimensions/measurements change, hopefully getting lower
To start generating you body fat chart, you will need to first enter your height. This can be entered from the "Edit Settings" option in the main page.
Then, you will need to enter your measurements, either weekly or monthly. Make sure you enter all the required data:
For men: Height (from settings), Neck and Waist
For women: Height (from settings), Neck, Waist and Hips.
Once there's enough sufficent data entered (minimum of one full set of data) , you can see your body fat progress chart from the "Edit measurements" menu option.
HTH