Macro Calculator
The CalorieJoy split is the evidence-based default - it scales protein and fat to your body instead of using fixed percentages.
Do you have chronic kidney disease or reduced kidney function?
We ask because kidney disease reverses the usual protein advice.
This calculator provides estimates for educational purposes only and is not medical advice. Results may vary based on individual factors. Consult a healthcare provider before making changes to your diet or exercise routine.
What are macros?
Macronutrients - protein, carbohydrates, and fat - are the three nutrients your body needs in large amounts. Each plays a different role: protein builds and repairs muscle, carbs provide energy, and fat keeps meals satisfying, carries the fat-soluble vitamins (A, D, E, K), and supplies the essential fatty acids your body cannot make.
Tracking macros goes beyond calorie counting by ensuring you get the right balance of nutrients for your specific goal — whether that's losing fat while keeping muscle, maintaining your current physique, or building mass.
The CalorieJoy method
Most macro calculators use fixed percentage splits, but a 60 kg woman and a 120 kg man on the same "40/30/30" get very different protein-per-kg ratios. Our CalorieJoy split scales to your body:
- Protein: scaled by activity - 1.6g/kg (sedentary) up to 2.1g/kg (super active), the same target for men and women
- Fat: at least 20% of calories or 0.6g per kg, whichever is higher - the floor that protects essential fatty acids, fat-soluble vitamin absorption, and satiety. The floor is grams, not a percentage: on a small calorie budget the fat percentage has to rise to protect those grams. And it is not about hormones - the research shows menstrual health tracks total energy intake, not dietary fat
- Carbs: whatever calories remain - your flexible energy source
Above BMI 30 we prescribe protein against adjusted body weight instead of actual weight - excess weight is mostly fat tissue, which needs very little protein, so scaling to actual weight would overshoot badly. If the calorie target is too small to fit both floors, the calculator says so instead of quietly showing numbers that do not add up.
How this calculator works
We calculate your Total Daily Energy Expenditure (TDEE) using the Mifflin-St Jeor equation, the one recommended by the Academy of Nutrition and Dietetics. For weight loss we size the deficit to your body - about 0.75% of body weight per week, kept between 250 and 750 calories per day - and never go below your resting metabolic rate or 1,200 calories (women) / 1,500 calories (men). For muscle gain we add 300 calories. The result is then split into protein, carbs, and fat based on your chosen macro ratio.
Already tracking calories? Our Daily Calorie Intake Calculator pairs well with this tool. And if you're new to calorie awareness, start with understanding calorie deficit.
Formulas and scientific references Mifflin-St Jeor equation (1990) for calories, protein at 1.6-2.2 g per kg scaled by training load, and a dietary fat floor of 20% of energy or 0.6 g per kg, whichever is higher. Carbohydrate is the remainder.
Sources
- Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO. A new predictive equation for resting energy expenditure in healthy individuals. American Journal of Clinical Nutrition, 1990;51(2):241-247
- Morton RW, et al. Meta-analysis of protein supplementation and resistance training (49 studies, n=1,863). Gains in fat-free mass plateau at a total intake of about 1.6 g/kg/day. British Journal of Sports Medicine, 2018;52(6):376-384 (correction published 2020;54(19):e7)
- Helms ER, Zinn C, Rowlands DS, Brown SR. A systematic review of dietary protein during caloric restriction in resistance trained lean athletes. International Journal of Sport Nutrition and Exercise Metabolism, 2014;24(2):127-138
- Jager R, et al. International Society of Sports Nutrition position stand: protein and exercise. Baseline 1.4-2.0 g/kg/day, higher during energy restriction in resistance-trained people. Journal of the International Society of Sports Nutrition, 2017;14:20
- World Health Organization. Total fat intake for the prevention of unhealthy weight gain in adults and children: WHO guideline (2023). Total fat should be at least 15-20% of total energy intake. World Health Organization, 2023
This calculator gives a general educational estimate, not medical or individualized nutrition advice. Prediction equations are wrong by more than 10% in roughly 1 in 3 people.