Free tool
Calorie Calculator: Daily Calories and Macros
Work out how many calories you need each day to lose fat, maintain, or build muscle, and how to split them into protein, carbs, and fat. It's the same formula the Miran app uses for your plan.
Moderate daily activity & exercise 3-4 days a week
Your daily target
1,804kcal / day
≈ 0.7 kg loss per weekMaintenance: 2,577 kcal
- Protein
- 158g
- Carbs
- 203g
- Fat
- 40g
The same formula the Miran app uses (revised Harris-Benedict). Estimates, not medical advice. Nothing you enter is sent or stored.
How the calculation works
Basal metabolic rate (BMR)
We start with the energy your body needs at complete rest, using the revised Harris-Benedict equation (Roza & Shizgal, 1984):
Men: BMR = 88.362 + 13.397 × weight(kg) + 4.799 × height(cm) − 5.677 × ageWomen: BMR = 447.593 + 9.247 × weight(kg) + 3.098 × height(cm) − 4.330 × ageMaintenance calories from your activity
BMR is multiplied by the activity factor that matches your week:
| Level | Description | Factor |
|---|---|---|
| Inactive | Little or no physical activity at all with zero days of exercising | × 1.1 |
| Lightly Active | Light daily activity & exercise 1-2 days a week | × 1.25 |
| Moderately Active | Moderate daily activity & exercise 3-4 days a week | × 1.4 |
| Very Active | Physically demanding lifestyle & exercise 5-6 days a week | × 1.55 |
| Extremely Active | Almost daily complex exercise/sports & Physically demanding lifestyle | × 1.7 |
Adjusting for your goal and splitting macros
Maintenance calories are adjusted for your goal, then split between carbs, protein, and fat:
| Goal | Calories | Carbs | Protein | Fat |
|---|---|---|---|---|
| Weight Loss | −30% | 45% | 35% | 20% |
| Shred | −20% | 45% | 35% | 20% |
| Overall Fitness | No change | 45% | 30% | 25% |
| Bulk | +15% | 55% | 25% | 20% |
Shares are then converted to grams: 4 kcal per gram of carbs or protein and 9 kcal per gram of fat.
Safety limits
- Targets never go below 1,500 kcal for men and 1,200 kcal for women.
- Under 18: maintenance calories only, with no deficit or surplus.
- These are estimates, not medical advice. Talk to a professional if you have a health condition.
Frequently asked questions
How many calories should I eat a day?
It depends on your body, activity level, and goal. The calculator estimates your maintenance calories (BMR multiplied by an activity factor) and adjusts them for your goal: a 30% deficit for Weight Loss, 20% for Shred, a 15% surplus for Bulk, and no change for Overall Fitness.
What is the difference between BMR and maintenance calories?
BMR (basal metabolic rate) is the energy your body uses at complete rest. Maintenance calories add your daily activity on top: BMR multiplied by an activity factor from 1.1 (inactive) to 1.7 (extremely active).
Why won't the calculator go below 1,200 or 1,500 calories?
Very low intakes are hard to sustain and can be unsafe without supervision, so targets never drop below 1,500 kcal for men and 1,200 kcal for women. Under 18, the calculator keeps you at maintenance calories.
How are the macros calculated?
Your calorie target is split between carbs, protein, and fat by goal (for example 45% / 35% / 20% for Weight Loss), then converted to grams: 4 kcal per gram of carbs or protein and 9 kcal per gram of fat.
Is this the same calculation as the Miran app?
Yes. It's the same formula the app uses for your plan. In the app, your logged activity is also taken into account.
Turn these numbers into a daily plan
In the Miran app you snap your meals to log their calories, follow your workouts, and get a nutrition and training plan built around your goal.