How Many Calories You Really Need: Formula to Calculate Your BMR

Calculating BMR
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One of the most common questions that I am asked is "how many calories should I eat?" and while many of us are hoping to hear that "magic number" of what is going to help us lose weight, the fact is our caloric needs are highly individual. Calculating your basal metabolic rate (BMR) is the simplest way to find the answer. Here's how it works

How to Calculate Your Daily Caloric Needs

Since every body type is different and the levels of individual activity and exercise are different, it's important to include those parameters in any formulas used to calculate specific caloric needs.

Your BMR is the amount of energy your body needs to function. We use about 60% of the calories we consume each day for basic bodily functions such as circulating blood to your body, pumping your heart and breathing. Your activity levels can be determined based on the frequency and number of days you are involved in sports or exercise.

The formula we use here is based on the Harris Benedict Equation, which multiplies your calculated BMR value by your personal activity level. The final number you are left with is the recommended daily calorie intake needed to maintain your current weight. If you are looking to lose weight, you would need to eat 300 to 500 fewer calories per day than your calculated daily caloric needs while maintaining or increasing your exercise activity.

Step One: Formula to Calculate BMR

Other factors that influence your BMR are height, weight, age and sex. (Please note that this formula applies only to adults.) The first step is to calculate your BMR with the following formula:

For Women:

655 + (4.3 x weight in pounds) + (4.7 x height in inches) - (4.7 x age in years)

For Men:

66 + (6.3 x weight in pounds) + (12.9 x height in inches) - (6.8 x age in years)

The resulting number of each equation is your BMR.

Step Two: Incorporate Activity Level to Calculate Calories Needed

In order to incorporate activity into your daily caloric needs, complete the following calculations.

If you are sedentary (little or no exercise)

Multiply BMR x 1.2

If you are lightly active (light exercise 1-3 days per week)

Multiply BMR x 1.375

If you are moderately active (moderate exercise 3-5 days per week)

Multiply BMR x 1.55

If you are very active (hard exercise 6-7 days a week)

Multiply BMR x 1.725

If you are extra active (very hard exercise and a physical job)

Multiply BMR x 1.9

Once you have determined your activity level and multiplied that number with your BMR, the resulting number is the number of calories you can comfortably consume each day without weight gain. If calculating the formula is not your cup of tea, you can find your daily caloric needs at a glance here.

Get Started

Ready to get started with losing weight by calorie counting? The helpful tools at ​Calorie Count can help you track your calorie needs and your calorie use throughout the day — for free!

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