How Many Daily Calories Do You Need? Guide According to your Objective
Published on 3 de marzo de 2026 | Recently updated
Calculate your daily calories based on your weight, height and activity. Learn how to adjust your intake to lose fat, maintain or gain muscle.
Why does it matter to know how many calories you need?
Calories are the unit of energy that our body uses to function. From breathing and thinking to running a marathon, everything requires energy. If you consume more calories than you expend, you accumulate fat; If you consume less, you lose it. Knowing your daily caloric requirement is, therefore, the first step to any weight-related goal, whether losing, gaining or maintaining.
It's not about counting each calorie obsessively, but rather having a clear reference that allows you to make informed decisions about your diet. With the Calorie Calculator With GlobalTool you can get a personalized estimate in seconds, taking into account your weight, height, age, gender and activity level.
How Basal Metabolic Rate (BMR) is Calculated
The basal metabolic rate is the minimum energy that your body needs at absolute rest to maintain vital functions: breathing, blood circulation, thermal regulation, etc. The most commonly used formula is the Mifflin-St Jeor equation:
Men: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5
Women: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161
This base value is multiplied by an activity factor to obtain the estimated total caloric expenditure (TDEE). If you need to convert your weight between pounds and kilos, use the Weight Converter before applying the formula.
Physical activity factors
| Activity level | Factor | Description |
|---|---|---|
| Sedentary | 1.2 | Office work, no exercise |
| Slightly active | 1,375 | Light exercise 1-3 days/week |
| Moderately active | 1.55 | Moderate exercise 3-5 days/week |
| Very active | 1,725 | Intense exercise 6-7 days/week |
| Extra active | 1.9 | Professional athlete or very physical job |
For a 30-year-old man, 80 kg and 1.78 m tall with moderate activity, the calculation would be: BMR = 1,780 kcal × 1.55 = 2,759 kcal/day. That figure is your maintenance; To lose weight you should reduce it, and to gain muscle mass, increase it.
Calories according to your goal: lose, maintain or gain weight
Once you know your TDEE, the adjustments are relatively simple:
- Lose fat: A calorie deficit of 15-25% (300-500 kcal less per day) is sustainable and minimizes the loss of muscle mass. At this rate, you can expect to lose between 0.3 and 0.7 kg per week.
- Maintain weight: consume approximately what you spend. It is the maintenance phase after reaching your goal.
- Gain muscle mass: A caloric surplus of 10-15% (200-350 extra kcal per day), combined with strength training, promotes muscle growth without accumulating excessive fat.
Practical advice
Do not reduce more than 500-600 kcal per day compared to your TDEE. Aggressive deficits slow down metabolism, cause muscle loss, and increase the likelihood of rebound effect.
To complement your calorie control, it is essential to know your current body composition. Check out our guide on what is BMI and how to calculate it to obtain a first indicator of your weight status. And if you need to adjust recipes or calculate ingredient proportions, the Rule of Three It will make conversions easier for you.
Common mistakes when counting calories
Although calorie control is effective, there are common pitfalls to avoid:
- Do not count liquids. Juices, soft drinks, alcoholic beverages and coffees with milk and sugar can add hundreds of invisible calories.
- Underestimate portions. Without weighing food, most people underestimate what they really eat by 20-40%.
- Overestimate exercise. Gym machines and apps tend to inflate calories burned. Be conservative in your estimates.
- Obsess over the exact number. The formulas are estimates; Use them as a starting point and adjust based on actual results on the scale.
- Ignore nutritional quality. 200 kcal of vegetables do not have the same metabolic effect as 200 kcal of industrial pastries.
To effectively track your diet and progress, combine calorie calculation with tracking your weight and measurements. If you want to go further in organizing your health, check out our article on useful online tools in 2026 to discover more free resources to help you along the way.
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