How do you know how much body fat you have? I see people posting their % but I do not know how they figure it? I've used one of those online calculators, but how could that possibly be accurate, all they ask for is height and weight, and frame size...

Its not accurate at all. One way to check BMI is skinforld calipers. Usually three sites are measured and plugged into a formula, combined with your weight and age your % is calculated. This is a service that is done at most gyms and its fairly accurate with a trained person.

I had a test done. It was done at a gym. I go back to the trainer tomorrow. Have a great day