The number of calories the body consumes in a day is different for every person. You may notice on the nutritional labels of the foods you buy that the "percent of daily values" are based on a 2,000 calories per day. But your body might need more or less than 2,000 calories. Height, weight, gender, age, and activity level all affect your caloric needs.

Your BASAL METABOLIC RATE (BMR) is the amount of energy your body needs to function at rest. This includes the energy required to keep your heart beating, lungs breathing, body temperature stable, etc.

Here is a very simple method of calculating your BMR:

  Use the following conversion chart assess your height in Inches:
Feet to Inches Conversion Chart
4'10=58" 5'2=62" 5'6=66" 5'10=70" 6'2=74" 6'6=78"
4'11=59" 5'3=63"' 5'7=67" 5'11=71" 6'3=75" 6'7=79"
5'0=60" 5'4=64" 5'8=68" 6'0=72" 6'4=76" 6'8=80"
5'1=61" 5'5=65" 5'9=69" 6'1=73" 6'5=77" 6'9=81"

To estimate your BMR, fill in your physical characteristics and click on Enter:

Physical characteristics
Age in years (yrs)
Weight in pounds (lbs)
Height in inches (in)
 
Your BMR
MEN
WOMEN

AMR (Active Metabolic Rate)
 To maintain normal bodily functions, your body "burns" more calories throughout the day than at rest. Once you have calculated your BMR above, you can enter the average minutes you spend in a variety of activities each day. The result is only an estimate, but should give you an idea of your daily caloric needs.

Physical Activity, minutes/day
Very Light
Light
Moderate
Heavy
Very Heavy
Examples include:
Reading
Sitting
Driving
Eating		 Examples include:
Walking
Sweeping
Playing Piano
Bicycling (easy) 		Examples include:
Fast walk
Dancing
Ping-Pong
Skating 		Examples include:
Swimming
Running
Bicycle Race
Basketball 		Examples include:
Boxing
Rowing
Mountain climbing
Total Energy Requirement
calories/day for men
calories/day for women
 
Calorie needs to lose weight


There are approximately 3500 calories in a pound of stored body fat. So, if you create a 3500-calorie deficit through diet, exercise or a combination of both, you will lose one pound of body weight. (On average 75% of this is fat, 25% lean tissue) If you create a 7000 calorie deficit you will lose two pounds and so on. The calorie deficit is best  achieved  by a combination of fewer calories in (healthy eating) and more calories out (exercise). This combination of healthy eating and exercise is best for lasting weight loss. Indeed, sustained weight loss is impossible without increased regular exercise.

If you want to lose fat, a useful guideline for lowering your calorie intake is to reduce your calories by at least 500, but not more than 1000 below your maintenance level.  As a guide to minimum calorie intake, the American College of Sports Medicine (ACSM) recommends that calorie levels never drop below 1200 calories per day. Even these calorie levels are quite low.

An alternative way of calculating a safe minimum calorie-intake level is by reference to your body weight or current body weight. Reducing calories by 15-20% below your daily calorie maintenance needs is a useful start.