Calculator Inputs
Example Data Table
| Profile | Goal | Calories | Protein | Carbs | Fats | Meals |
|---|---|---|---|---|---|---|
| 78 kg, moderate activity | Maintain | 2,630 | 156 g | 296 g | 73 g | 4 |
| 68 kg, light activity | Lose fat | 1,870 | 150 g | 170 g | 52 g | 4 |
| 90 kg, very active | Gain muscle | 3,430 | 162 g | 451 g | 86 g | 5 |
Formula Used
1. Basal metabolic rate: Mifflin-St Jeor estimates resting calories.
BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5 for men, or −161 for women.
2. Maintenance calories: TDEE = BMR × activity factor.
3. Goal calories: calorie target = TDEE ± goal adjustment. Faster cuts use larger deficits. Lean gains use smaller surpluses.
4. Protein: grams = body weight in kg × protein target. Recommended values increase during fat loss to protect lean mass.
5. Fat: fat grams = (target calories × fat percentage) ÷ 9.
6. Carbohydrates: carb grams = remaining calories ÷ 4 after protein and fat calories are assigned.
How to Use This Calculator
- Enter your age, sex, weight, height, and unit system.
- Select the activity factor that matches your average weekly movement.
- Choose whether you want to lose fat, maintain weight, or gain muscle.
- Pick a pace. Moderate settings are easier to maintain long term.
- Use the recommended protein option or enter your own grams per kilogram target.
- Set fat percentage and meals per day based on preference.
- Click calculate to display calories, macros, meal splits, and estimated weekly change above the form.
- Download the results as CSV or PDF for tracking, coaching, or meal planning.
FAQs
What is flexible dieting?
Flexible dieting focuses on hitting calorie and macro targets while allowing varied food choices. It values consistency, portion control, and sustainability over rigid food rules.
Why is protein higher during fat loss?
Higher protein can improve fullness and help preserve lean tissue during calorie deficits. That makes cuts easier to maintain while supporting training recovery.
How often should I update my macros?
Review your averages every two to three weeks. If bodyweight and measurements stall, adjust calories slightly instead of changing everything at once.
Are carbs or fats better for energy?
Both matter. Carbs usually support training performance better, while fats support hormones and satiety. The best split depends on your preferences and routine.
Can I use this calculator without body fat percentage?
Yes. Body fat is optional here. The calculator still estimates calories and macros using weight, height, age, sex, activity, and goal.
What if my carb value seems very high?
That usually happens when protein is moderate and fat is set lower. Carbs receive the remaining calories after protein and fat are assigned.
Is this a medical nutrition prescription?
No. It is an educational planning tool. Anyone with diabetes, kidney disease, pregnancy, or active treatment needs should use clinician guidance.