How to Calculate Your Daily Calorie Needs

Harris-Benedict Formula

A more accurate way to calculate your daily calorie needs is to determine basal metabolic rate (BMR) using multiple factors, including height, weight, age and gender, then multiply the BMR by an activity factor to determine your total daily energy expenditure (calories). One calculation method is the Harris Benedict formula.

The Harris-Benedict Formula

The Harris Benedict equation is a calorie formula using the variables of height, weight, age, and gender to calculate basal metabolic rate (BMR). This is more accurate than calculating calorie needs based on total body weight alone. The only factor it omits is lean body mass and thus the ratio of muscle-to-fat a body has. Remember, leaner bodies need more calories than less leaner ones. Therefore, this equation will be very accurate in all but the very muscular (Harris-Benedict will under-estimate calorie needs) and the very fat (Harris-Benedict will over-estimate calorie needs).

Two Steps to Determine Daily Calorie Needs

First, determine your BMR.

Second, apply the Activity Multiplier.

Harris Benedict Formula for Women – STEP 1

BMR = 655 + (9.6 X weight in kilos) + (1.8 X height in cm) – (4.7 X age in years).

Notes:

1 inch = 2.54 cm.

1 kilogram = 2.2 lbs.

Example of BMR

You are 32 years old

You are 5 feet 4 inches tall (162.5 cm)

Your weight is 185 pounds (84 kilos)

Your BMR is 655 + (806) + (291) – (150) = 1602 calories

Harris Benedict Formula for Women – STEP 2

To determine your total daily calorie needs, now multiply your BMR by the appropriate activity factor, as follows:

If you are Sedentary – little or no exercise

Calorie-Calculation = BMR X 1.2

If you are Lightly Active (light exercise/sports 1-3 days/week)

Calorie-Calculation = BMR X 1.375

If you are Moderately Active (moderate exercise/sports 3-5 days/week)

Calorie-Calculation = BMR X 1.55

If you are Very Active = BMR X 1.725 (hard exercise/sports 6-7 days/week)

Calorie-Calculation = BMR X 1.725

If you are Extra Active (very hard daily exercise/sports & physical job or 2X day training)

Calorie-Calculation = BMR X 1.9

Total Calorie Needs Example

If you are sedentary, multiply your BMR (1602) by 1.2 = 1922

Your total daily calorie requirement is therefore 1922 calories.

This is the total number of calories you need in order to MAINTAIN your current weight.

If you wish to lose or gain weight, click these links:

Calorie Needs to Lose Weight

Calorie Needs to Gain Weight

Harris Benedict Formula for Men

BMR = 66 + (13.7 X weight in kilos) + (5 X height in cm) – (6.8 X age in years)

Notes:

1 inch = 2.54 cm.

1 kilogram = 2.2 lbs.

Example of BMR

You are 25 years old

You are 6 feet tall

Your weight is 220 pounds

Your BMR is 66 + (1370) + (914) – (170) = 2180 calories

Harris Benedict Formula for Men – STEP 2

To determine your total daily calorie needs, now multiply your BMR by the appropriate activity factor, as follows:

If you are Sedentary – little or no exercise

Calorie-Calculation = BMR X 1.2

If you are Lightly Active (light exercise/sports 1-3 days/week)

Calorie-Calculation = BMR X 1.375

If you are Moderately Active (moderate exercise/sports 3-5 days/week)

Calorie-Calculation = BMR X 1.55

If you are Very Active = BMR X 1.725 (hard exercise/sports 6-7 days/week)

Calorie-Calculation = BMR X 1.725

If you are Extra Active (very hard daily exercise/sports & physical job or 2X day training)

Calorie-Calculation = BMR X 1.9

Total Calorie Needs Example

If you are lightly active, multiply your BMR (2180) by 1.375 = 2997

Your total daily calorie requirement is therefore 2997 calories.

This is the total number of calories you need in order to MAINTAIN your current weight.

How Many Calories Do You Need to Lose Weight or Gain Weight

Now you know what your calorie-needs are, find out how many calories you need each day in order to lose or gain weight.

Calorie Needs to Lose Weight

Calorie Needs to Gain Weight

Information About Weight Control and Weight Loss