How the macro calculation works
Calories drive the overall direction of weight change. Protein supports muscle retention and growth, dietary fat supports normal nutrition, and carbohydrates fill the remaining energy budget. This tool sets protein at 2.2g per kilogram of bodyweight on a cut and 1.8g per kilogram at maintenance or on a lean bulk, both inside the 1.8 to 2.2 g/kg range generally supported for resistance-trained adults. Fat is held at a 25% floor so essential fatty acid and hormone-related intake stays covered, and carbohydrates absorb whatever calories remain after protein and fat are reserved.
Worked example
At 2,400 calories and 75kg on a cut: protein is 75 × 2.2, or 165g (660 kcal); fat is 25% of 2,400, or 600 kcal (67g); the remaining 1,140 kcal becomes 285g of carbohydrate. Raise the same profile to maintenance and protein drops to 75 × 1.8, or 135g (540 kcal), while fat stays at 600 kcal, leaving 1,260 kcal, or 315g, for carbohydrate. Recalculating this way after every meaningful calorie change keeps protein and fat anchored while carbohydrate does the adjusting.
Adjusting your macro plan
Keep the plan steady long enough to observe a trend, usually two to three weeks. If progress is not moving in the intended direction, adjust calories modestly and recalculate rather than constantly changing every macro.
Frequently asked questions
- How are macros calculated?
- Protein and carbohydrate each provide about 4 calories per gram; fat provides about 9. This tool reserves protein and fat first, then assigns remaining calories to carbohydrates.
- Are the targets exact?
- No. They are a practical starting point. Track your trend and adjust calories before making large macro changes.
- Why does protein range from 1.8 to 2.2 g/kg?
- Research on resistance-trained adults generally supports 1.6 to 2.2 g/kg of bodyweight daily for muscle retention and growth. This tool uses 2.2 g/kg on a cut, where a higher intake helps protect lean mass in a deficit, and 1.8 g/kg at maintenance and on a lean bulk, where the deficit-driven catabolic pressure is absent.
- Why is fat fixed at 25% of calories instead of a range?
- Dietary fat below roughly 20 to 25% of calories risks under-supplying essential fatty acids and can affect hormone production. Fixing fat at 25% keeps a floor in place automatically; carbohydrates absorb the calorie changes between a cut, maintenance, and a bulk instead.