Enter the Basal Metabolic Rate and Physical Activity Level into the calculator to determine the daily energy intake. This calculator can also evaluate any of the variables given the others are known.

Energy Intake Formula

The following formula is used to calculate the daily energy intake.

EI = BMR * PAL

Variables:

  • EI is the daily energy intake (kcal)
  • BMR is the Basal Metabolic Rate (kcal/day)
  • PAL is the Physical Activity Level (unitless)

To calculate the daily energy intake, multiply the Basal Metabolic Rate by the Physical Activity Level. The Basal Metabolic Rate is the amount of energy expended while at rest in a neutrally temperate environment, in the post-absorptive state (meaning that the digestive system is inactive, which requires about 12 hours of fasting in humans). The Physical Activity Level is a way to express a person’s daily physical activity as a number, and it is used to estimate a person’s total energy expenditure.

What is an Energy Intake?

Energy intake refers to the amount of calories or energy a person consumes through food and drink. This energy is essential for the body to perform various functions such as maintaining body temperature, supporting physical activities, and promoting growth and repair of body tissues. The recommended energy intake varies depending on factors like age, sex, weight, height, and physical activity level.

How to Calculate Energy Intake?

The following steps outline how to calculate the Energy Intake (EI) using the formula EI = BMR * PAL.


  1. First, determine the Basal Metabolic Rate (BMR) (kcal/day).
  2. Next, determine the Physical Activity Level (PAL) (unitless).
  3. Next, gather the formula from above = EI = BMR * PAL.
  4. Finally, calculate the Energy Intake (EI) (kcal).
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

Basal Metabolic Rate (BMR) (kcal/day) = 1500

Physical Activity Level (PAL) (unitless) = 1.5