Resting metabolic rate can be found by calculating your basal metabolic rate (BMR). There are a variety of online calculators for this. As a rough estimate, it will be around your body weight multiplied by 12. From there, you should add calories based on your daily activity. Diets should never drop below your BMR. Metabolism can vary from individual to individual, so it's a good idea to asses caloric intake, depending on how you progress after a couple of weeks.
- Erin Stern, 2x Ms. Figure Olympia