Split calories into protein/carbs/fat.
These calculators use established formulas (such as Mifflin-St Jeor for calorie needs or the Devine formula for ideal weight) to provide general estimates. They're built for a general population and don't account for individual medical conditions, medications, or circumstances. They aren't a substitute for advice from a doctor, registered dietitian, or other qualified healthcare provider — especially for anything related to pregnancy, chronic conditions, or medication dosing.
Splits a daily calorie target into grams of protein, carbs, and fat. Protein and carbs = 4 kcal/g, fat = 9 kcal/g.
Common splits: 30/40/30 balanced, 40/20/40 low-carb, 40/35/25 high-protein. Protein 1.6–2.2 g/kg supports muscle maintenance in a deficit.
The specific ratio matters less than hitting your total calorie target consistently and getting enough protein — carb and fat ratios can flex quite a bit based on personal preference and still support the same overall goal.
2,200 kcal balanced (30/40/30) = 165 g protein, 220 g carbs, 73 g fat.
Sedentary ~0.8 g/kg. Active or in deficit: 1.6–2.2 g/kg. Elderly: higher end to preserve muscle.
Weight loss depends on calorie deficit, not carb ratio. Low-carb helps some people control appetite, but scale moves on calories.
±10% is fine. Trends matter more than any single day.
Higher protein generally helps during a calorie deficit to preserve muscle; higher carbs can support performance during intense training blocks. Adjust gradually rather than switching structure abruptly.