This is an estimate of how many calories you need to eat in a day to maintain your weight.
Decrease your caloric intake by 250-500 calories a day. Aim to lose 1-2 pounds of fat per week to be sure you aren't losing muscle mass.
Note: Your calories should not drop below 1200 calories a day if you're a woman or 1800 calories a day if you're a man. Decreasing your caloric intake too drastically will cause you to lose muscle and hold onto fat.
You want to gradually reduce calories week by week. Only reduce if fat loss stalls.
Increase your caloric intake by 500 calories a day. Aim to gain 1-2 pounds a week to keep fat gain minimal.
Your BMR (Basal Metabolic Rate) is calculated, and then your activity level is added to determine your total daily calories using the Harris Benedict Equation.