First off any calcultor should be used a a start point, it is not gospel so make sure results are monitored and you try to be as honest when calculating as possible.
As for the calculator to use, I also recommend the Harris Benedict...
Start by getting your BMR-
http://www.bmi-calculator.net/bmr-calculator/
then times that by your activity level
http://www.bmi-calculator.net/bmr-ca...dict-equation/
subtract or add from that number is you need to lose or gain.