I use fitness pal, its very useful as can also track the fat too....you set a daily toatal...so 45g.
As a womans daily recommended calories for maintenance is 1950 kcal to loose weight you need to aim for less, but not too much or your body can think you're starving it and hold on to it.
My daily total is 1500/1600 kcal, with the exercise I seem to be doing ok, put on last week due to muscle gain from commencing exercise, but 1.5 Ib off this week, should get better now muscle there as that ways double to fat.
If you tell fitness pal what weight you are and that you want to loose 2Ib a week it will set a recommended daily kcal for you.