fotorieCalculate Caloric Deficit: Calculator and Guide
Choose how much you want to cut and you will see how many calories you need per day, how much you can lose per week, and how many weeks you need to reach your target weight. With the safety floor applied by Vitasane nutritionists.
Indicative estimate for adults. Not recommended during pregnancy or lactation; if you have an illness or need individual guidance, consult a professional. About the limitations of weight planners (NIDDK).
That deficit would put you below the reference threshold. We have raised the calories to the calculator\'s threshold and recalculated the rate with the actual remaining deficit.
Calculation with Mifflin-St Jeor and the equivalence of 7,700 kcal per kilo of fat. This is an estimate: during pregnancy, lactation, for minors, or with a pathology, the deficit should be set by a professional.
What is caloric deficit
Caloric deficit occurs when you eat less energy than you expend. The body covers the difference by drawing on its reserves, especially fat, and weight decreases. No diet leads to weight loss without this mechanism, no matter what it\'s called: the Mediterranean, keto, intermittent fasting, or pineapple diets only work when they make you eat less than you expend.
To calculate your caloric deficit, you need two numbers: what you expend per day, which we call maintenance calories, and what you decide to cut. The calculator above estimates the first with your data (or you can enter it if you already know it from the daily calorie calculator) and applies the second.
How much deficit is reasonable
The question is not how much deficit leads to faster weight loss, but how much you can maintain during the months a real weight change takes. These are the three ranges that Vitasane nutritionists use in consultation, and those offered by the calculator:
| Daily deficit | Weekly loss | For whom | How long |
|---|---|---|---|
| 250 kcal | 0.2-0.3 kg | Few kilos to lose, people who get hungry easily, first weeks to build the habit | Can be maintained for months without effort |
| 500 kcal | 0.4-0.5 kg | Most people: between 5 and 20 kilos overweight | 2 to 4 months, with one maintenance week every 6-8 |
| 750 kcal | 0.6-0.8 kg | Only with a lot of weight to lose and high protein; better with supervision | No more than 6-8 consecutive weeks |
Another way to look at it is in percentage: a deficit of 15% to 20% of your maintenance is the point where loss is noticeable and hunger is manageable. Below 10%, the scale moves so slowly that it\'s hard to keep going; above 30%, the body starts to defend itself.
This calculator uses reference thresholds of 1,200 kcal for women and 1,500 for men. These are not universal minimums nor do they guarantee that a diet is sufficient or adequate for you. If the calculation reaches that threshold, review the goal with a professional before applying it.
Why 500 kcal per day is half a kilo per week
One kilo of fatty tissue contains about 7,700 kcal. With a 500 kcal deficit per day, you accumulate 3,500 per week, which is about 450 grams of fat. This is the rule behind almost all calculators and works well as an order of magnitude, with two nuances worth knowing:
- The first two weeks the scale drops more. By eating fewer carbohydrates, part of the glycogen is emptied, and each gram of glycogen carries three grams of water. That initial kilo or kilo and a half is not fat and does not repeat.
- Over time, the pace slows down. When you weigh less, you expend less, and the body also slightly reduces expenditure due to adaptation. Every 4 or 5 kilos lost, recalculate your maintenance and adjust.
With this, the calculator gives you the weeks until your target weight. Take it as a reasonable forecast, not a deadline: if you lose a little less than expected, you are not doing anything wrong.
Signs that the deficit is excessive
A well-planned deficit is barely noticeable. If several of these signs appear, the cut is greater than your body can currently tolerate:
- Hunger that is not satisfied with a normal meal, especially at night.
- Fatigue during training and loss of strength in exercises that used to be easy.
- Cold hands and feet, poor sleep, increased irritability.
- Stagnation of the scale for three consecutive weeks despite compliance.
- Loss of contour in arms and legs more than in the waist: you are losing muscle.
- In women, menstrual cycle alterations. This sign requires slowing down and consulting a professional.
The solution is almost never to endure. It is to increase by 200 or 300 kcal, especially protein and carbohydrates around training, and to include a full maintenance week every six or eight. You lose weight a little slower, but you continue to lose, which is what matters.
Protein in deficit
When you eat less, the body doesn\'t choose where it gets energy from: it draws from fat and also from muscle. The way to protect it is twofold: strength training two or three times a week and eating enough protein, between 1.8 and 2.2 grams per kilo of body weight per day. For 70 kg, that\'s 125 to 155 grams, distributed over three or four meals.
Protein also has another advantage in a deficit: it is the most satiating nutrient per calorie. A plate with 40 grams of protein and vegetables satisfies hunger much better than the same number of calories in bread or fruit. How to distribute the rest between carbohydrates and fats depends on your goal and what feels good to you; you have it with estimated grams in the macro calculator.
Putting it into practice is the hardest part. Fotorie calculates your deficit with these same rules, creates a weekly menu that already balances protein, and counts each meal from a photo of the plate, without searching or weighing. In calorie counter we tell you how.
Frequently asked questions
How much caloric deficit is needed to lose weight?
Between 300 and 500 kcal per day below your maintenance is the range that works best: you lose around half a kilo per week without feeling hungry or losing muscle. Deficits of 750 kcal or more only make sense with a lot of weight to lose and with good protein intake, and not for months on end.
Why do 500 kcal per day equal half a kilo per week?
One kilo of body fat stores about 7,700 kcal. If you spend 500 kcal more than you eat each day, in a week you accumulate 3,500 kcal of deficit, slightly less than half a kilo of fat. This is an approximation: at first, the scale drops faster due to water and glycogen, and over time the body adapts and the pace slows down.
Can you create a caloric deficit without counting calories?
Yes, if you have a clear reference. Reducing portions of bread, oil, and alcohol, filling half your plate with vegetables, and prioritizing protein usually generates a 300-500 kcal deficit without tracking anything. An app that estimates the plate with a photo gives you that reference without weighing.
What happens if the deficit is too large?
Constant hunger, fatigue, cold, poor sleep, irritability, stagnation after a few weeks, and muscle mass loss. If you notice several of these signs, increase your intake by 200-300 kcal and prioritize protein: you will lose weight a little slower but you will continue to lose.
How much protein should you eat in a deficit?
Between 1.8 and 2.2 grams per kilogram of body weight per day. In a deficit, protein protects muscle and is the most satiating nutrient, so it should be the last thing to cut back on. This website's macro calculator gives you the estimated grams.
Make it automatic: photo and done
Fotorie sets your deficit with nutritionist criteria, counts each meal with a photo, and its coach alerts you when you overeat or undereat. Free to start.
