Body fat calculator:
http://www.scientificpsychic.com/fitness/diet.html
I don't think it looks right though, because on another calculator, I got 31% body fat :/
Body Mass Index: 17.6 kg/m2
Waist-to-Height ratio: 0.39
Percent Body Fat: 16.9%
Lean Body Mass: 37.4 kg
You are underweight...