What is the Harris-Benedict calorie calculator?

The Harris-Benedict calorie calculator estimates your daily calorie needs based on your Basal Metabolic Rate (BMR) and activity level.

How does the Harris-Benedict formula work?

It calculates your BMR using your age, gender, weight, and height, then multiplies it by an activity factor to estimate total daily calorie needs.

What is Basal Metabolic Rate (BMR) in the Harris-Benedict formula?

BMR is the number of calories your body needs to maintain basic physiological functions like breathing and circulation while at rest.

Why is the Harris-Benedict calculator useful?

It helps you understand your calorie needs for maintaining, losing, or gaining weight based on your activity level.

What is the difference between the original and revised Harris-Benedict formulas?

The revised formula, updated in 1984, is more accurate as it accounts for modern data on energy expenditure.

How do I determine my activity level for the Harris-Benedict calculator?

Activity levels range from sedentary (little or no exercise) to very active (intense daily exercise), which influence the calorie multiplier.

Is the Harris-Benedict calculator accurate?

It provides a reliable estimate, but individual factors like metabolism and muscle mass can affect actual calorie needs.

Can the Harris-Benedict calculator be used for weight loss?

Yes, it helps you determine a calorie deficit by estimating how many calories you need to maintain weight.

Harris-Benedict Calorie Calculator

Harris Benedict calorie calculator

Your gender:

Enter your age

Enter your height

Enter your weight

Select your activity level:

Select your goal:

Level	kcal/day

This is a reliable calculator to estimate daily calorie consumption in a person. The Harris-Benedict formula was designed for this purpose. This automatic calculator uses the Harris-Benedict formula to estimate your total daily caloric expenditure. You can also estimate the calories needed to gain or lose weight, as well as to gain muscle.

The Harris Benedict equations for estimating basal energy expenditure were developed in the early 20th century from research at the Nutrition Laboratory of the Carnegie Institution of Washington, under the direction of Francis G. Benedict, with the aim of establishing reference standards for comparing the basal energy expenditure of people with different diseases (2).

How to use our Harris-Benedict calculator 2024?

The Harris – Benedict formula was developed in 1918. This formula is used to calculate the calories needed for basal metabolism and physical activity. Specifically, the most commonly used variant is the one proposed by Mifflin and St Jeor in 1990 based on a revision of the original. Represents the Basal Metabolic Rate (BMR), also known as Basal Metabolic Rate, which is the amount of energy needed to maintain the body’s vital functions at rest. This formula takes into account factors such as gender, weight, height, and age. Counting calories is critical, as there is no single variable more important for controlling obesity than daily caloric intake (3).

A fundamental principle of nutrition and metabolism itself is that body weight change is associated with an imbalance between the energy content of the food consumed and the energy used by the body to maintain basic processes, such as keeping us alive, in addition to all the movement performed. (4)

Based on this premise, whatever our goal, whether it is to lose, gain, or maintain our weight, we must know two data: our caloric expenditure, in order to subsequently perform a calorie count adapted to our goals.

This Harris Benedict calculator allows you to calculate the number of calories required for basal metabolism as well as the expenditure caused by daily physical activity, being one of the most used today. It also includes a variable that allows you to calculate, depending on the goals, the calories that should be consumed to lose weight, maintain weight, or increase it. The Harris-Benedict formula is widely used to calculate the daily calories required for both basal metabolism and physical activity. This equation has evolved, and the one most commonly used today is the one revised by Mifflin and St. Jeor in 1990, based on an update of the original.

In summary, the Harris-Benedict formulas are useful for estimating the daily calories needed for basal metabolism and, by extension, for calculating the Daily Energy Expenditure based on activity factors. Next, we will explore this formula, its applications, limitations, and other alternatives that may be useful for athletes and people who want to control their weight.

Explanation of the Harris-Benedict formula

Fundamentals of the Harris Benedict calculator

The fundamentals of the original formula are based on the measurement of the basal metabolic rate, where Harris and Benedict developed the equations using data from indirect calorimetry, which is a method that measures the exchange of respiratory gases in order to calculate the amount of energy the body consumes at rest (1).

Harris and Benedict relied on four main factors:

Body weight (in kg), reflecting the amount of body mass that requires energy to maintain.
Height (in cm): which represents a component of body size.
Age (in years), because it was observed that the basal metabolic rate decreases with age.
Gender: due to physiological differences between the two.

The original formula is as follows (1):

Gender	REE Formula
Men	REE = 66.5 + (13.75 × weight in kg) + (5.003 × height in cm) – (6.755 × age in years)
Women	REE = 655.1 + (9.563 × weight in kg) + (1.850 × height in cm) – (4.676 × age in years)

The Harris-Benedict formula provides what is known as Basal Metabolic Rate (BMR), which shows the amount of calories (energy) needed to maintain the body’s vital functions at rest.

This equation considers gender, age, weight, and height to calculate basal metabolism and, from there, estimates total caloric expenditure. There is one equation for men and another for women:

•⁠ Men: BMR= 66+(13.75×weight in kg)+(5×height in cm)−(6.75×age in years)

•⁠ Women: BMR= 655+(9.56×weight in kg)+(1.85×height in cm)−(4.68×age in years)

In 1990, as mentioned earlier, this equation was modified by Mifflin and St. Jeor, who updated the formula to improve its accuracy: The current formulas are:

•⁠ Men: BMR= (10×weight in kg)+(6.25×height in cm)−(5×age in years)+5

•⁠ Women: BMR = (10×weight in kg)+(6.25×height in cm)−(5×age in years)−161

Although these formulas are very popular, it is important to keep in mind that they are approximations and may not fit perfectly for every individual. However, individual variations and limitations in their applicability may occur, especially for athletes and people with high physical activity. In such cases, it is advisable to consider alternatives, such as the more recent formulas of Mifflin and St. Jeor, as well as specific formulas for athletes that take into account lean body mass.

There are more accurate tools and methods, such as indirect calorimetry, that can provide more exact estimates.

Comparison with other formulas

In this section, we will make a comparison between the most common formulas for calculating energy expenditure and caloric requirements.

Differences between Harris-Benedict and Mifflin-St Jeor

If we compare the Harris Benedict calculator and the Mifflin-St Jeor formula, we find that the Harris Benedict equation is suitable for predicting resting energy expenditure at the group level, but at the individual level, both methods present clinically significant differences (5).