buffroMacro Calculator
Calories decide whether you gain or lose. Macros decide how much of it is muscle. Get all four numbers in one place.
Fat: 78 g (702 kcal)
Carbs: 380 g (1520 kcal)
How it works
The calculator finds your TDEE with the Mifflin-St Jeor equation, applies your goal (cut −20%, maintain, bulk +10%), then splits those calories: protein first at 1.8 g/kg, fat at 25% of calories, carbs with whatever is left.
Example: an 80 kg lifter cutting on 2,240 kcal gets 144 g protein, 62 g fat, and about 277 g carbs.
The order of priority
Total calories decide the direction of the scale. Protein affects how much of the change is muscle. The carbs-to-fat split mostly comes down to personal preference and training performance. Do not stress that split until calories and protein are consistent.
Cut, maintain, and lean-bulk examples
An 80 kg lifter maintaining near 2,800 kcal can keep 144 g protein and roughly 78 g fat, leaving about 380 g carbs. A 20% cut lowers calories to 2,240, so protein stays at 144 g while carbs and fat make room. A 10% lean bulk lands near 3,080 kcal. The useful pattern is simple: protect protein and move total calories gradually.
Recalculate after a meaningful weight change, then judge the target by two to three weeks of average scale weight and gym performance. A formula is the opening estimate; your trend is the correction.
FAQ
What are macros?
The three nutrients that carry calories: protein (4 kcal/g), carbs (4 kcal/g), and fat (9 kcal/g). Tracking macros instead of just calories keeps your muscle fed while you cut or bulk.
How does this calculator split my calories?
Protein is set at 1.8 g per kg of bodyweight, fat at 25% of total calories, and carbs fill the remainder. It's a proven default for lifters, adjust fat and carbs to preference, keep protein fixed.
Do I have to hit my macros exactly?
No. Within about 5-10 g of each target is plenty. Protein is the one to prioritize, treat carbs and fat as flexible as long as total calories stay on target.
Should I eat different macros on rest days?
You can keep them identical and be fine. Some lifters shift 20-30 g of carbs from rest days to training days; it's a refinement, not a requirement.
Why is my carb number low?
Carbs are the remainder after protein and fat, so a deep cut with high protein leaves less room. If carbs feel too low to train well, trim fat toward 20% of calories and give the difference to carbs.
What macros should I use for bodybuilding?
Start with calories matched to the phase, protein around 1.6-2.2 g per kg of bodyweight, fat around 20-30% of calories, and carbs filling the rest. Bodybuilding does not require a special ratio; consistent calories, enough protein, and progressive training matter more.