1. Basal metabolic rate
The energy your body uses at rest, from the Harris-Benedict equation. Women: 655.1 + 9.563 × weight (kg) + 1.85 × height (cm) − 4.676 × age. Men: 66.47 + 13.75 × weight + 5.003 × height − 6.755 × age.
Calorie calculator
How many calories do you need a day? This calculator uses the same maths as the ClemCam app: your basal metabolic rate (Harris-Benedict), your activity factor and your goal. You also get protein, carbs and fat in grams.
Your calorie targetExample
1,442 calories a day
Protein136 g · 38% of calories
Carbs134 g · 37% of calories
Fat40 g · 25% of calories
- BMR
- 1,476 kcal
- Activity factor
- × 1.35
- Daily energy use
- 1,992 kcal
- Goal
- −550 kcal a day · −0.5 kg a week
Your plan in ClemCam.
The app does the same maths when you sign up and shows you every day what is left: calories in the ring, protein, carbs and fat next to it. Log meals by photo, text or search.
How the calculator works
2. Daily energy use
BMR times an activity factor, which stands for everything you move on top: the walk to work, the stairs, your workouts.
3. Goal
A kilogram of body fat is about 7,700 kcal. To lose weight the calculator plans 0.5 kg a week, so 550 kcal less a day. To gain weight 0.4 kg (440 kcal more), to build muscle 0.25 kg (275 kcal more). To keep your weight it stays at your daily energy use.
4. Macros
Protein follows your weight: 2.0 g per kg to lose weight, 1.8 g to build muscle, 1.6 g to gain weight, 1.4 g to keep it. Fat covers 25% of calories (30% to gain weight) and carbs the rest.
Activity factors
| Activity | Activity factor |
|---|---|
| Lightly active Little movement, hardly any exercise | 1.2 |
| Moderately active Exercise 1 to 2 times a week | 1.35 |
| Active Exercise 3 to 5 times a week | 1.5 |
| Very active 6 times a week or more | 1.7 |
Good to know
Every formula is an estimate. Your real needs can be a few hundred calories higher or lower. Check your weight after two to three weeks and adjust the target. The calculation does not apply during pregnancy or breastfeeding, to children and teenagers, or with medical conditions; talk to your doctor instead.
Questions
How many calories do I need a day?
It depends on your height, weight, age, sex and how much you move. A 30-year-old woman who is 168 cm tall, weighs 68 kg and exercises once or twice a week uses about 1,992 calories a day according to Harris-Benedict. Enter your own values above to see yours.
How many calories should I eat to lose weight?
For 0.5 kg a week, about 550 calories less than you use. The calculator subtracts that from your daily energy use. Bigger deficits are hard to keep up and tend to cost muscle.
What is the difference between BMR and daily energy use?
BMR is what you need at complete rest. Daily energy use adds everyday movement and exercise; the calculator models it with the activity factor.
How much protein do I need?
Depending on your goal, the calculator plans 1.4 to 2.0 g of protein per kilogram of body weight. It is highest when losing weight, because protein keeps you full and helps you keep muscle.