How many calories do you need a day? (And to lose about 0.5 kg a week)
Find out in seconds how many calories you need per day to lose fat, maintain or build muscle. We compute your basal metabolism and total expenditure (TDEE) with the Mifflin-St Jeor formula and give you a realistic target plus a macro split.
Sex
Goal
Estimate based on the Mifflin-St Jeor formula. Guidance, not medical advice.
You have your target. Now the hard part
Hitting it daily. Photograph your plate and the app subtracts it from your target — no weighing, no searching.
Next time you sit down to eat, photograph the plate before the first bite. That is the whole method.
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How are your calories calculated?
First we estimate your basal metabolic rate (BMR) — the energy you burn at rest — with the Mifflin-St Jeor equation, the most accurate of the common formulas in validation studies. We multiply that by your activity level to get your total daily energy expenditure (TDEE), which is simply your maintenance calories. Then we adjust for your goal: to lose fat we subtract about 500 kcal, a healthy pace of roughly 0.5 kg per week, and to build muscle we add about 275 kcal so the gain stays mostly lean. Finally we split the macros: protein by body weight (1.8 g/kg while cutting or bulking, 1.4 g/kg at maintenance), 25% of calories from fat, and carbohydrates take the rest.
Calories a day by weight and sex (kcal)
What a 35-year-old burns in a day, by body weight: at rest, with a sedentary life and training 3 to 5 days a week. The last column is what that same active person would eat to lose about 0.45 kg a week. Men at 1.75 m and women at 1.65 m.
| Profile (age 35) | At rest | Sedentary | Active (3-5 days) | Active, −500 kcal |
|---|---|---|---|---|
| Man · 70 kg | 1624 | 1949 | 2517 | 2017 |
| Man · 80 kg | 1724 | 2069 | 2672 | 2172 |
| Man · 90 kg | 1824 | 2189 | 2827 | 2327 |
| Woman · 55 kg | 1245 | 1494 | 1930 | 1430 |
| Woman · 65 kg | 1345 | 1614 | 2085 | 1585 |
| Woman · 75 kg | 1445 | 1734 | 2240 | 1740 |
Computed with the same function as the calculator: Mifflin-St Jeor (1990) × 1.2 if sedentary or × 1.55 if you train 3 to 5 days. The 500 kcal deficit is about 0.45 kg a week under the 7,700 kcal per kilo rule, and never goes below the safety floor: 1,200 kcal for women, 1,400 for men or 110 % of BMR. These are reference ranges for healthy adults, not a diagnosis or individual advice.
FAQ
How many calories do I need a day at 70 or 80 kg?
It also depends on your sex, age, height and how much you move. For a 35-year-old, 1.75 m man: at 70 kg, 1,949 kcal if sedentary and 2,517 if he trains 3 to 5 days; at 80 kg, 2,069 and 2,672. A 65 kg, 1.65 m woman: 1,614 and 2,085. The calculator estimates your own figure from your details.
How many calories to lose 0.5 kg a week?
Take about 500 kcal off your maintenance: that is 3,500 kcal a week, roughly 0.45 kg under the 7,700 kcal per kilo rule. For an active 80 kg man it comes to 2,172 kcal a day; for an active 65 kg woman, 1,585. The calculator never goes below a safety floor (1,200 kcal for women, 1,400 for men), and much bigger deficits cost muscle and make the rebound more likely.
What are maintenance calories (TDEE)?
The total you burn in a day: your basal metabolism plus everyday movement plus exercise. Eat around your TDEE and your weight holds; below it you lose, above it you gain. It is the starting point for any goal, which is why the calculator shows it separately.
Is this calculator accurate?
It is a good estimate, but no equation is right for everyone — real expenditure varies by 10-15% between people with identical stats. Treat it as a starting point and let reality correct it: if after 2-3 weeks the scale is not moving as expected, adjust by 100-200 kcal. Tracking and adjusting beats any formula.
Keep reading
- How many calories should I eat a day →
- How to count calories without going crazy →
- Caloric deficit for beginners →
- How to calculate your macros →
- How to choose a calorie counting app →
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