Calorie Calculator
How many calories do you need a day? Find your maintenance calories and daily targets to lose or gain weight, from your age, sex, height, weight and activity.
| Goal | Calories a day | Change a week |
|---|
For healthy adults. These are estimates, not medical advice. Ask a doctor or dietitian about your own targets — especially if you are pregnant, have a health condition or are under 18.
How your calorie needs are calculated
The calculator first estimates your basal metabolic rate (BMR) — the energy your body uses at rest — with the Mifflin-St Jeor equation, then multiplies it by an activity factor to get your total daily energy expenditure (TDEE).
BMR (women) = 10 × kg + 6.25 × cm − 5 × age − 161
calories a day = BMR × activity factor (1.2 – 1.9)
Example: a 35-year-old man, 175 cm and 75 kg, has a BMR of about 1,674 kcal. With moderate exercise (× 1.55) he needs about 2,594 kcal a day to keep his weight.
Calories to lose or gain weight
A common rule of thumb is that about 7,700 kcal equals 1 kg of body fat (3,500 kcal per pound). Eating 550 kcal a day below your maintenance level therefore leads to about 0.5 kg of weight loss a week. Real weight change slows over time as the body adapts, so treat the numbers as a starting point.
Don’t go too low
Below about 1,500 kcal a day for men and 1,200 kcal for women, it becomes hard to get enough protein, vitamins and minerals from food. Very low-calorie diets should only be followed with medical supervision. The calculator marks targets below these levels.
Activity levels
| Activity | Factor |
|---|---|
| Sedentary (desk job, little exercise) | 1.2 |
| Light exercise 1–3 days a week | 1.375 |
| Moderate exercise 3–5 days a week | 1.55 |
| Hard exercise 6–7 days a week | 1.725 |
| Physical job or training twice a day | 1.9 |
Frequently asked questions
How many calories should I eat a day?
It depends on your age, sex, size and activity. Most adults need roughly 1,800–2,400 kcal (women) or 2,200–3,000 kcal (men). The calculator gives a personal estimate.
How many calories to lose 0.5 kg (1 lb) a week?
About 500–550 kcal a day below your maintenance calories.
Which BMR formula does the calculator use?
Mifflin-St Jeor, which studies found to be the most accurate of the common equations for most adults.