How Many Calories Do You Need?

There are a number of formulas for predicting approximately how many calories a person needs on a daily basis to remain at the same weight, including the following, called the Mifflin–St. Jeor equations, which calculate your basal metabolic rate (BMR):

  • For men, BMR = (10 × weight) + (6.25 × height) – (5 × age) + 5
  • For women, BMR = (10 × weight) + (6.25 × height) – (5 × age) – 161

These equations require your weight in kilograms, height in centimeters, and age in years. To calculate your weight in kilograms, divide your weight in pounds by 2.2. To calculate your height in centimeters, multiply your height in inches by 2.54.
Next, multiply your BMR by one of the following numbers, according to your usual activity level. This will determine your total daily calorie needs:


Sedentary: 1.3

Lightly active: 1.4

(walking or standing but no formal exercise)

Moderately active: 1.5

(some exercise)

Very active : 1.6

(walking and exercise)

Extra active: 1.8

(very hard daily exercise or sports, a physically active job, or training two times a day)