How Many Calories for a 115-lb. Person?

"How many calories should I eat to lose weight — or even to maintain or gain?" One eating plan definitely doesn't fit all, even within the same weight class. If you weigh 115 pounds, any calorie intake calculator you consult will also consider other variables.

Read more: Are There Certain Foods That Will Help You Gain Weight in Your Thighs and Buttocks?

It's common to be asked to specify your level of physical activity to help determine how many calories you need. The Mayo Clinic's online form, for example, lists four categories. "Inactive" describes a person with a fairly sedentary lifestyle, while "somewhat active" refers to someone who does some level of activity a couple of times a week, such as going for a walk.

To be considered "active," you'll need to be working out at a moderate level for a half-hour most days, or for 20 minutes, at an intense level, a few days a week. The highest level, "very active," is reserved for athletic people who work out for long periods every day.

For women under 50, of average height and weight, the ideal calorie range is between 1,800 and 2,200, depending on how active they are, according to the American Academy of Family Physicians. But because 115 pounds is a lower-than-average-weight, that ideal skews a bit lower for maintenance.

For example, a 35-year-old woman of average height who is "somewhat active" should consume about 1,700 calories. The total range for her age group is between 1,550 and 2,150 calories, depending on how often she works out.

Read more: How Many Calories Can You Continue to Burn After a Workout?

Age and height are also important factors in picking the right meal plan for yourself. After age 50, a sedentary woman should lower her intake by about 200 calories a day to maintain her weight. For most women, that would mean taking in about 1,600 calories a day.

But a 115-pound woman's calorie intake should be about 1,450 when she is less active and over 50, according to the Mayo Clinic calorie intake calculator. (Ideally, she should also work with her doctor to plan a more active lifestyle.)

If you are over 50, get a fair amount of exercise and weigh 115 pounds, aim for 1,600 to 1,750 calories for weight maintenance. If you're very active or training for a marathon, on the other hand, bump your caloric intake up to 2,050.

While current weight is more important than height for putting together a meal plan, how tall you are is still a variable considered by the calorie intake calculator. A 6-foot tall woman should eat about 50 more calories for her activity level than a woman who is also 115 pounds, but who is only 5 feet tall.

You may have decided you'd like to gain or drop a few pounds. In order to do this safely, aim for about 1 pound of gain or loss a week, advises the American Council on Exercise (ACE).

"How many calories should I eat to lose weight?" In terms of the mathematics of weight loss, you'll need to change your caloric daily intake by decreasing what you consume by 500 calories each day. Rather than cutting 500 calories from what you eat, however, ACE advises reducing your food calories by 250, and aiming to burn about 250 more calories each day through activity.

Of course, not every day will present an opportunity for a longer workout. There may also be days during which you eat more calories than your current target. That's why it helps to know ACE's formula: for the week, a 3,500 calorie decrease will result in a 1-pound loss. This allows you to work out longer on alternate days, rather than every day, for example, or to plan a lighter eating day once or twice a week.

To gain weight, don't give up a healthy workout schedule just for the sake of adding calories. Instead, try to add up to 500 calories a day through your diet. If that feels like too much of a challenge for your appetite, aim for adding 250 calories a day, and putting on the weight more gradually.