Plan your daily nutrition

Macro Calculator

Get a practical daily calorie, protein, carbohydrate, and fat target for your current goal.

Calculate your daily macros

Units
Goal

How FitCalc builds your macros

FitCalc estimates calories with the Mifflin–St Jeor equation and your selected activity level, then applies a 15% fat-loss reduction, no maintenance adjustment, or a 10% muscle-gain increase. You can instead supply your own calorie target.

Protein is allocated first at FitCalc's practical high-protein target, fat receives the greater of 0.6 g/kg or roughly 25% of calories, and carbohydrate receives the remaining calories. This is a planning split—not a uniquely perfect ratio.

Macros for fat loss and muscle gain

Fat loss requires an energy deficit, while gaining muscle is generally better supported near maintenance or in a modest surplus. Protein supports tissue maintenance and training adaptation; dietary fat supplies essential fatty acids and supports normal physiology; carbohydrate is a flexible energy source, especially around activity.

What happens when calories are too low?

The calculator never creates negative carbohydrate or fat. If calories cannot support the preferred protein and fat setup, it shows a visible warning so you can reconsider the target rather than treating a constrained split as ideal.

Limitations

These are educational estimates for adults, not medical nutrition therapy. Energy expenditure and food tracking contain meaningful uncertainty. Pregnancy, lactation, kidney disease, eating disorders, and other clinical situations require individualized professional guidance.