Suntan12-I have heard of that. I know that the last time I had by fat measurement taken was at a local gym that used a skin fold testing technique.
At the time I had 18% body fat which I was really proud of. A body density calculator really allows you to see the percentage of body fat you have as well as what the norm is.
Most men should have a body fat percentage of 20% or less in order to be considered healthy. This is because they have a higher percentage of lean muscle mass than women do.