Calories are not the major factor in weight gain or loss. Some high calorie foods are great for weight, such as fatty fish. The biggest factor is how you metabolize what you eat into sugar and how well you digest what you eat. I don't think any calorie calculator will help you lose weight, but basically, if you increase the output of energy you will probably lose weight. If you cut down on the amount you eat without eliminating the healthy foods you will probably lose weight. Slowly. Eat less, exercise more is still pretty basic, but it still depends a lot on what it is you're eating and also what it is you do for exercise.