Calculating calorie requirements: the most important questions and answers

Kalorienbedarf berechnen: Die wichtigsten Fragen und Antworten

Are you unsure how to calculate your calorie needs or don't even know how high your daily calorie needs are? Are you afraid of eating too many or too few calories? Are you on a specific diet and want to lose or gain weight? If you don't know how many calories you should consume each day to reach your personal goal, you've come to the right place with your questions.

This guide is intended to show you how to correctly calculate your daily calorie requirement. This way you can keep track of how many calories you need per day and whether you are actually covering your calorie requirements correctly. Here you get tips for calculating your calorie needs and information about your basic needs, your calorie consumption and the right calorie intake.

the essentials in brief

  • Your daily calorie requirement is made up of your basal metabolism and your performance metabolism. The result describes the total turnover and indicates the actual calorie requirement of your body.
  • The daily calorie requirement of a person cannot be generalized and depends on gender, age, height, weight and activity. In order to calculate the correct calorie requirement, all factors must be considered.
  • Depending on whether you want to lose or gain weight, a calorie deficit or calorie surplus is used when calculating the calorie requirement. Your total sales serve as a guide.

Calculating calorie requirements: which factors you should consider and what you should know

Below you will find an overview of how your daily calorie requirement is made up and how you can easily calculate it. Before we give you our tips and information on how to calculate your calorie requirement, we will explain which basic factors you should consider when calculating. We will then answer all frequently asked questions about calculating calorie requirements in the following paragraphs.

How many calories do I burn in a day?

The body burns energy all the time, even when sitting and even sleeping. The necessary energy is drawn from our food, with the calorie determining how much energy can be extracted from a nutrient during digestion. But how much energy does each person need?

The metabolism and the cardiovascular system already need a lot of energy to keep the body alive. Then there is the energy requirement for each individual movement or sporting activity that you do. The daily calorie requirement of a person is calculated from the basal metabolic rate and the performance turnover that you accomplish in one day. The total turnover then describes your actual calorie requirements.

basal metabolic rate

The basal metabolic rate only indicates how many calories your body uses daily at complete rest and to maintain vital functions. So your body uses those calories even if you lay in bed all day or move very little.

Breathing, maintaining body heat and the cardiovascular system also require energy.

The calorie basal metabolic rate includes all natural physical processes that take place without active control, but for which your body needs a certain amount of energy every day. The basal metabolic rate is calculated using the Harris-Benedict formula, a formula suitable for everyday use that was developed in 1918 and is still considered a renowned standard formula today. (1)

  • Basal metabolic rate men: 66.47 + (13.7 * body weight in kg) + (5 * height in cm) – (6.8 * age in years)
  • Basal metabolic rate women: 655.1 + (9.6 * body weight in kg) + (1.8 * height in cm) – (4.7 * age in years)

The individual basal metabolic rate and daily requirement of your body is influenced by numerous factors and is different for every person. The basal metabolic rate is determined by age, gender, height and weight. But muscles or pregnancy also ensure that the basal metabolic rate increases.

performance turnover

Physical activity does not play a role in calculating the basal metabolic rate. At this point, the power turnover is added. The power turnover describes the additional amount of energy that is used by sport or other activities.

The higher the activity level, the higher the calorie requirement.

Depending on how strong your physical activity is, your performance turnover also varies. People who are very active in their everyday life and job and do a lot of sport have a significantly higher power turnover than people who are rather inactive in sports and spend most of their time sitting.

The performance conversion can be calculated using the so-called PAL factor (Physical Activity Level). The PAL value expresses your personal activity level and indicates the number you need to multiply your basal metabolic rate by to calculate your total energy requirement.

Power turnover = basal turnover x (PAL factor – 1)

To get the correct PAL factor for your bill, the relevant factors are multiplied by the number of hours of your activity and added together. The sum is then divided by 24 to get the average daily factor. (2)

PAL factor activity
0.95 Sleep
1.2 sitting or lying down
1.4 - 1.5 Sedentary only, little activity
1.6 - 1.7 Predominantly sedentary with standing and walking activity
1.8 - 1.9 Mostly standing and walking activity
2.0 - 2.4 Physically strenuous activity

total sales

The sum of the basal metabolic rate and the performance metabolic rate indicates how high your total calorie requirement is for the day. The total turnover therefore indicates how many calories you can consume per day without causing a change in your weight. The specific calorie requirement differs between men and women, and the body's metabolic function also changes with age. (3)

In the following we have a table for you that shows you a guide value for the daily energy requirement depending on age and gender. The values ​​in the table are given in kilojoules (kJ) and kilocalories (kcal) and describe the calorie requirements of people with relatively little physical activity. (4)

Old Men Women
15 - 19 years 10,460kJ / 2,500kcal 8,370kJ / 2,000kcal
19 - 25 years 10,460kJ / 2,500kcal 7,950kJ / 1,900kcal
25 - 51 years 10,040kJ / 2,400kcal 7,950kJ / 1,900kcal
51 - 65 years 9,200kJ / 2,200kcal 7,530kJ / 1,800kcal
from 65 years 8,370kJ / 2,000kcal 6,700kJ / 1,600kcal

What are the calorie needs of children?

The calorie requirement of a child differs significantly from that of an adult. The calorie requirement of children also depends on how much energy the child consumes during the day and how high the activity level is, which means that orientation based on a fixed table does not always make sense. The basal metabolic rate of a child who moves little or not at all is therefore significantly lower than that of a child who does significantly more sport and has a correspondingly higher calorie requirement.

Children's daily calorie needs decrease in relation to their weight. During the growth phase in childhood, a baby needs around 90 kcal per kilogram of body weight. The child needs enough calories to grow healthily and to develop all important bodily functions.

This value is reduced by about half until adolescence, even if the absolute value of the energy required increases significantly with increasing age. From the age of 18 to 19, the calorie requirement gradually decreases again, so it is important to adjust your eating habits accordingly from this point on.

How can I calculate my individual calorie requirement?

The daily calorie requirement depends on the composition of the body and is therefore very individual from person to person. The energy requirement is influenced by different factors such as gender, age, size, type of work and all activities.


To calculate your daily calorie needs, all you need is the Harris-Benedict formula and the correct PAL factor. You put all the relevant values ​​of your body into the formula and calculate your basal metabolic rate. (Image source: Karolina Grabowska / pexels)

For a calculation that is as accurate as possible using the given formulas, it is important to take into account the biological sex, age, height and weight. You can find out here what influence these factors have on your calorie requirements.

  • Gender: On average, men have more muscle mass than women, heavier bones and less body fat than women , resulting in higher calorie needs. Even when at rest and with little activity, a man burns more calories than a woman. Because of this, men can consume more calories and lose weight faster than women.
  • Age: With age, the metabolic functions are optimized, which means that the body requires less energy with increasing age. Muscle mass also decreases with age. Metabolic function has a significant impact on basal metabolic rate.
  • Size: People who are particularly small have a significantly lower basal metabolic rate than people who are particularly tall, since both the size and the body mass that needs to be supplied are different.
  • Weight: In order to determine the individual calorie requirement, the ratio of fat and muscle mass is particularly important when it comes to weight. The weight of your body has an impact on how much energy your body needs to move it during activities, for example.
  • Activity: All activities and sporting activities are added to the basal metabolic rate. How high your individual calorie requirement is therefore depends heavily on the type and duration of your activity.
  • Goal: Depending on whether you have the goal of losing weight or gaining weight and building muscle, your individual calorie requirement results from a calorie deficit or a calorie surplus. In order to maintain your weight, you should cover your calculated calorie requirement exactly.

In addition to the given factors that affect your body, your physical activity and your goals also have a decisive influence on the determination of your calorie needs. Do you do sports in your free time, or are you already physically active at work, or do you spend too much time in the office and at your desk?

How is the calorie requirement calculated when losing weight?

Anyone who calculates their daily calorie requirement in order to lose weight often asks themselves: how many calories can I eat per day in order to lose weight? When it comes to losing weight, it's important to create a calorie deficit so that the calories burned out exceed the amount of calories you take in. Just the opposite: If you take in more calories than your body uses, you gain weight.

The optimal calorie requirement for losing weight is roughly in the middle of your basal metabolic rate and your total requirement. If you save too many calories, your body falls into a kind of energy-saving mode because it is no longer supplied with enough nutrients and your metabolism slows down. It's not always good to lose weight quickly . Even a moderate deficit of 300 to 500 calories is enough to lose weight healthily in the long term. (5.6)

Important: Not all calories are the same.

A study published in the journal Public Health Nutrition shows that while it is important to consider your personal calorie needs, not every calorie is created equal. Instead of just focusing on quantity, it's even more important to pay attention to the quality of calories when trying to lose weight.(8)

One kilogram of body fat corresponds to approximately 7000 calories.

If your goal is to lose weight, you should not only pay attention to calculating your calorie needs to create a deficit, but also to the foods themselves. The energy value of a food does not always indicate the effect of the product on the body. Foods with a high fat content are usually higher in calories, but are not always bad for the body.

Healthy fats in nuts, olive oil, whole milk or fish are far healthier than starchy or high-sugar foods, despite the high number of calories.

How is the calorie requirement calculated when building muscle?

In contrast to losing weight, the energy supply required for muscle building behaves differently. If you want to build muscle, you need to consume more calories than you expend. Your body needs the extra energy to develop new muscle tissue. However, the increased supply of energy requires that you do weight training regularly, otherwise you will only gain fat and not the desired muscle mass. (9)

Healthy eating and sports

The basis for every diet, but also for every muscle building phase, is to know exactly how many calories and macronutrients you can or must eat. Since the calories themselves are not the only important factor for healthy muscle building, you should also pay attention to high-quality protein sources and the correct intake of carbohydrates. (Image source: zuzyusa / pixabay)

With a calorie surplus of 300 to 500 calories a day and additional muscle training, your body can efficiently build muscle mass and supply the new tissue with sufficient nutrients.

How is the calorie requirement during pregnancy calculated?

During pregnancy, in addition to her own basic needs, the child in the womb of the pregnant woman must also be taken care of, which is why the woman's calorie requirement increases during this time. Especially during this time it is important to take in enough nutrients with food so that the baby can grow up healthy. But here, too, the basic requirement depends on the stature and weight of the woman as well as the performance. If you tend to be underweight during pregnancy, you need a higher calorie intake than if you are normal weight or overweight.

Although the body needs additional nutrients for the baby, your calorie requirements do not double.

The calorie requirement during pregnancy can be divided into three phases. In general, the calorie requirement is lowest in the first trimester of pregnancy, i.e. between the 1st and 12th week of pregnancy. Here you should cover your daily needs and not aim for any diets or the like.

Only in the second third and up to the 27th week does your calorie requirement increase by an average of 250 to 300 calories a day. From the 28th week and in the last trimester of pregnancy, the calorie intake should be increased by around 500 calories in order to be able to provide the baby with sufficient nutrients. This information will also vary depending on whether you are expecting multiples or just one baby. (10)

If you were already overweight before pregnancy, the above information does not apply. Your body can cover the increased calorie requirements caused by pregnancy from its own reserves. But that doesn't mean you should lose weight during pregnancy. When body fat is broken down, bound pollutants and hormones can be released, which then reach your child. So it is not a matter of trying to go on an additional diet, but rather using the reserves that you already have. (11)

How do I calculate my calorie needs if I'm overweight?

The decisive factor for the basal metabolic rate is not necessarily the total weight, but rather the proportion of biologically active tissue that drives metabolic activities. In connection with the basal metabolic rate and obesity, the proportion of metabolically inactive tissue is far higher in overweight people than in normal-weight men and women. For this reason, you have a lower basal metabolic rate when you are overweight than when you are normal weight.

If you are overweight, the daily energy intake should be about a third less than the actual calorie consumption. With a total daily turnover of 2240 kcal, you should calculate two thirds of this, which means that you can consume around 1500 kcal. With this calculation, your weight loss would be 1 kg of body fat tissue per week.

That doesn't seem to be much if you're overweight, but losing weight faster would be unhealthy for your body in the long term. If you take in too few calories despite having excess reserves, you lose not only fat but also muscle mass and body water, which in turn lowers your basal metabolic rate. (12)

To eat healthy food

You can only achieve long-term success with a consistent and permanent change in your eating habits and lifestyle. Especially if you are overweight, it is important to choose your food carefully in order to make it as low in fat and rich in nutrients as possible. High-fiber foods have a higher degree of satiety and prevent food cravings during the diet. (Image source: Ella Olsson / unsplash)

In order to avoid a yo-yo effect when you are overweight, you should not reduce your calorie intake too drastically, since such rapid weight loss is usually short-lived and you often even gain more weight later than before. This yo-yo effect is not only frustrating in the long run, but also harmful to your body. As soon as you have reached your normal weight, you should make sure that your energy intake and your daily energy requirement are roughly balanced in order to maintain the weight.

Calculating calorie requirements: What alternatives and tools are there?

Now you know how to calculate your daily calorie requirement yourself and what factors it is made up of. In the following, we will show you which alternatives are available for calculating calorie requirements and how you can do the writing and calculating yourself.

Since many people try to pay attention to their daily calorie requirements and like to record their performance and activities, there are specially developed fitness apps and fitness trackers as well as fitness watches that record your calorie consumption all by themselves and thus calculate your calorie requirements. We will show you the different ways to have your daily calorie needs displayed and explain how they work.

Fitness trackers and smart watches

Fitness trackers and smartwatches on the wrist should measure your daily performance. Algorithms convert movement data into step counts and the intensity of endurance runs and activities is measured based on the rising and falling heart rate.

However, since your calorie consumption is influenced by many different and very individual factors, you should know that such fitness trackers can never provide accurate measurement data on calorie consumption, since individual values ​​such as muscle mass, BMI , state of health or fitness level can only be recorded approximately or not at all . Fitness trackers are therefore not precise measuring devices, which is why you should understand the information on calorie consumption as a guideline. (13)

fitness tracking

Fitness trackers measure your power consumption based on your heart rate and can thus determine exactly how many calories you are currently consuming. Values ​​such as weight and height can often be easily entered in an associated app. (Image source: Ketut Subiyanto / pexels)

The reason for incorrect information about calorie consumption or incorrect processing of the data is usually missing basic data. To ensure greater accuracy, most fitness trackers and smartwatches work with an additional app in which you should definitely enter precise data about your body. This allows the tracker to directly include your height and weight when calculating your calorie consumption during exercise. (14)

online calculator

On the Internet you will find numerous online calculators that will easily calculate your energy requirements. On most sites, all you have to do is provide information about the important factors that determine your basal metabolic rate in order to have your basal metabolic rate output electronically. Once you have entered your height, weight, age and gender, the site will automatically calculate your daily calorie needs.

There are often extra columns in which you can enter information about your activity level. There you can either enter exact activities with a corresponding duration, without having to calculate the PAL factor yourself beforehand, or select which profession you practice, whereby the program can calculate how active your everyday life is.

With such online calculators, the computer only does the math for you and calculates your calorie needs in the same way that you can calculate them yourself. Since the Benedict Harris formula is also used here and the PAL factors are used to calculate your performance and total sales, the calculation is not more accurate here either. The statement of your calorie requirement will probably be the same as with a standalone and manual calculation.


In this guide you have learned that you cannot generalize about a person's calorie requirement and that it is calculated from a combination of different factors. Important factors that provide information about the calculation of calorie needs are age, gender, height and weight. In addition to your general basal metabolic rate, you can also calculate how many calories you burn in your daily activities.

The method of calculating calorie needs serves different purposes. You can calculate your calorie needs to create a calorie deficit that will help you lose weight or a calorie surplus that will help you build muscle or gain weight. In general, however, you should not deviate too much from your daily calorie requirements, since after all your body needs a certain amount of energy and nutrients to stay healthy.


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