There's a great tool on the Prevention Magazine web-site. Under weight loss, there is a daily calorie counter. You put in the weight you would like to be, then your height, age, sex, activity level and then it calculates how many calories you should eat a day to maintain that weight. It surprised me how many calories I can eat a day. Here's an example--
For a male that is 6'2" 37 years old, lightly active and say wanted to weigh 210 pounds-- His daily calorie intake should be 2,726 calories.
It is nearly impossible to be the weight you want to be and not know how many calories you should eat a day. This tool makes it simple. Handy huh?