How many calories a day to lose weight: how to find your number

What to expect in this article

1. What matters when losing weight
2. Your baseline: total energy expenditure
3. How large the deficit should be
4. Four steps to finding your number
5. Three misconceptions about your daily calorie intake
6. Whether genetic analysis can help you
7. What is realistic in 6 to 12 months
8. Where the calculation reaches its limits
9. Your number and what to do with it
Frequently asked questions
Sources

What matters when losing weight

The question of the right number of calories sounds as though the number is listed somewhere in a table. It is not. What exists is a principle—and from that principle, your personal number can be derived.

The sentence sounds banal, and that is precisely its strength. It also tells us what is not decisive: not the time of your last meal, not the order in which you consume nutrients, and not a single forbidden food. What matters is the balance over time.

This gives us the structure of any meaningful calculation. On one side is your energy expenditure; on the other is your intake. Your weight-loss calorie target is the intake that falls below your expenditure—and to determine it, you first need to know your expenditure.

Why blanket figures can be misleading

Guides often cite figures such as 1,500 kilocalories for women and 2,000 for men. Such figures are averages from a very large group. They fit no one in particular and not even approximately many people.

Two people with the same weight can have significantly different energy expenditures due to age, muscle mass, and above all, physical activity in everyday life. Anyone who adopts a blanket figure will therefore either calculate too generously or too narrowly. Both lead to frustration, just from different directions.

Calculating it yourself is straightforward: two figures, one multiplication, and a deduction. It takes five minutes and gives you a number that applies to you, not to a statistical average.

Your starting point: total energy expenditure

Total energy expenditure is the amount of energy that maintains your weight. It consists of two factors: resting metabolic rate and an activity factor, the PAL value.

According to the German Nutrition Society, the resting metabolic rate is calculated using a formula based on weight and age—for women, (0.047 × kg − 0.01452 × age + 3.21) × 239, and for men, (0.047 × kg + 1.009 − 0.01452 × age + 3.21) × 239. You multiply the result by the PAL value that matches your activity.

The PAL value is the part you estimate yourself—and therefore the part where most mistakes occur. The following overview shows what the levels mean and how much they shift the result. A resting metabolic rate of 1,392 kilocalories is used throughout as the example calculation.

PAL values and sports supplement: German Nutrition Society (DGE). The example calculations are based on a resting metabolic rate of 1,392 kcal and are rounded. The last two lines are editorial context, not information provided by the DGE.

The last sentence is why taking care at this point is more worthwhile than fine-tuning the formula. Choosing the wrong PAL level shifts the result by several hundred kilocalories—and therefore by more than the size of a typical deficit.

If you would like to follow the calculation of your total calorie needs step by step, you can find a detailed explanation in our article How do I calculate my calorie needs?. Here, the result is enough: a number that maintains your weight.

How large the reduction should be

This is where many guides become imprecise, so here is the honest answer: The source material used for this article gives no fixed figure for the ideal daily deficit. The commonly cited rule of thumb of 500 kilocalories appears in many texts, but not in the sources cited here—so it is not presented here as substantiated.

The sources provide the result. According to IQWiG, people who participated in structured weight-loss programs lost approximately 3 to 8 kilograms within 6 to 12 months, averaging about 5 to 6 kilograms (as of 2022). This provides an indication of the expected range.

What these figures mean per week

Spread the average 5 to 6 kilograms over half a year to a full year, and you arrive at approximately half a kilogram to one kilogram per month, distributed over many weeks. That is considerably less than most people plan to lose when they start—and considerably more than they achieve when they give up in frustration after four weeks.

For your approach, this means choosing a moderate reduction rather than a drastic one. A deficit you can maintain for six months beats one you can maintain for three weeks—even if the latter appears faster on paper.

The practical consequence: Set the reduction so that you can manage the resulting amount of food without a daily struggle. And plan a check-in after four weeks from the outset, when you can adjust upward or downward depending on what the scale shows.

There is also a lower limit. Very low calorie intakes over an extended period require medical supervision and should not be managed independently. If your own calculation produces a figure that is significantly below your resting metabolic rate, you have either calculated incorrectly or planned too ambitiously.

Find your number in four steps

The order matters here: Each step requires the result of the previous one. Have your weight, age, and a calculator ready; the entire process takes less than ten minutes.

The fourth step is the one most people skip—and the one that turns an estimate into a reliable number. The formula provides a starting value; the scale provides the correction. Only together do they give you your actual calorie target.

A note about weighing yourself: Daily fluctuations of one to two kilograms are normal and say nothing about your progress. They are caused by fluid levels, salt intake, and digestion. The scale only becomes meaningful over several weeks—which is why the schedule is every four weeks rather than daily monitoring.

Three misconceptions about your daily calorie intake

Assumptions surrounding calorie targets can lead either to drastic measures or to giving up too soon. Three of them are worth correcting.

Whether a genetic analysis can help you

The calculation above provides a number. It does not answer the question of what you fill that number with – whether you cope better with more carbohydrates or more fat, and how your body responds to endurance or strength training. This is exactly where genetic analyses come in, and exactly where an honest assessment is worthwhile.

The order matters: The calculation comes first, and the analysis may follow. Anyone who starts with the test while leaving the energy balance unaddressed will end up with lots of information about their predisposition but still no number to use as a guide.

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What is realistic over 6 to 12 months

Study figures are not a promise for any individual case, but they are the best available benchmark for setting your own expectations. The results cited by IQWiG provide that benchmark.

Participants in structured weight-loss programs lost about 3 to 8 kilograms over 6 to 12 months, averaging around 5 to 6 kilograms. Programs using formula diets led to greater weight loss of about 10 to 15 kilograms. Those who were also physically active had lost nearly two kilograms more after twelve months than those who only changed their diet (IQWiG, as of 2022).

How to interpret these figures for yourself

The range of 3 to 8 kilograms is almost more important than the average. It shows how differently people respond to the same approach—and that a result at the lower end is not a personal failure, but part of the observed range.

The significantly higher values for formula diets should also be interpreted with caution. They refer to supervised programs and say nothing about how much of the loss is maintained after the program ends. The yo-yo effect mentioned by IQWiG is the relevant limitation here.

And the nearly two kilograms attributable to physical activity may be the most practical figure of all. It is small enough not to portray exercise as a miracle cure, yet large enough not to dismiss it. Regular exercise also shifts your PAL value and therefore the baseline of your calculation.

Where the calculation reaches its limits

The first limitation lies in the formula itself. It only accounts for weight and age, not your body composition. Two people who weigh the same but have different amounts of muscle mass are assigned the same resting metabolic rate, even though their actual rates differ.

The second limitation concerns intake. Calorie figures on packaging are average values with legally permitted tolerances, portions are estimated, and the oil used in the pan is regularly forgotten. If you set your deficit too narrowly, estimation errors alone can erase it.

The third limitation concerns time. Your PAL value changes, often unnoticed: a job change to working from home, a break due to injury, a move with a shorter commute. The figure that was right in January may be outdated by June—which is why you need a recurring checkpoint rather than a one-time calculation.

The first three limitations are no reason to abandon the calculation—but they are a reason to interpret it correctly. It provides an estimate, not an exact value. Anyone who treats it as an estimate and adjusts it based on their progress will get further than someone who plans to within ten kilocalories and abandons the entire approach at the first estimation error.

And a fourth: There are situations in which the calculation is not the right starting point. In the case of existing medical conditions, during pregnancy and breastfeeding, with a history of eating disorders, or when weight is lost without trying, the matter belongs in the hands of a doctor—not in an online formula.

Your figure and what to do with it

There is no calorie figure that applies to everyone, and trying to find one takes more time than doing your own calculation. Resting metabolic rate multiplied by PAL value gives you your energy needs; a moderate reduction gives you your figure.

What this figure provides is a reliable starting point. What it does not provide is accuracy to the kilocalorie—there are too many estimates involved. That is why reviewing your progress over four weeks is not an add-on, but the second part of the method.

Your specific next step: Calculate your resting metabolic rate today, choose a PAL level one step more cautiously than you would rate yourself, and note the date and your starting weight. In four weeks, you will know whether your figure is right—and that is more than any blanket recommendation can tell you.

Frequently asked questions

Sources

1. Institute for Quality and Efficiency in Health Care (IQWiG): Weight-loss programs and medications, as of 2022 — gesundheitsinformation.de
2. German Nutrition Society (DGE): Selected questions and answers about energy intake — dge.de
3. Institute for Quality and Efficiency in Health Care (IQWiG): Causes of obesity, as of 2022 — gesundheitsinformation.de

The quotation on the principle of weight loss, the loss of 3 to 8 or an average of 5 to 6 kilograms over 6 to 12 months, the 10 to 15 kilograms with formula diets, the nearly two kilograms through physical activity, and the statement about the yo-yo effect come from source [1]. Both formulas for resting energy expenditure, all PAL levels, and the sports supplement of 0.3 units are based on source [2]. The classification that muscle mass, age, and height influence resting energy expenditure comes from source [3]. The example calculations are based on these figures and rounded. None of the three sources gives a figure for the size of a daily calorie deficit; the corresponding classification in the article is identified as an editorial deduction. Product information comes from the mybody®x product pages, accessed on August 5, 2026.

mybody®x Editorial & Expert Team

Nutritional science Energy metabolism Nutrigenetics

This article was created and medically reviewed by the mybody®x Editorial and Expert Team. The team brings together expertise in nutrigenetics, microbiome and gut science, blood test interpretation, nutritional science, and laboratory diagnostics.

Published on August 5, 2026 · Last updated on August 5, 2026

Medical notice: This article is intended for general information and does not replace medical advice, diagnosis, or treatment. If you have existing medical conditions, are pregnant or breastfeeding, have a history of eating disorders, or are experiencing unintended weight loss, any dietary change should be medically supervised.