Macro Calculator
Inputs
Need help? Estimate it with the U.S. Navy calculator .
3–4 purposeful sessions.
Aggressive but sustainable deficit.
Good all-round macro split.
Aim for 34 g protein per feeding window.
Your macros
BMR
1699 kcal Mifflin–St JeorMaintenance (TDEE)
2633 kcal Moderate factor ×1.55Target calories
2106 kcal Fat loss −20%Lean mass basis
Fiber target
Meal idea (x4)
Sources
- Mifflin MD, St Jeor ST, et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr. 1990;51(2):241–247. PMID 2305711 — basis for the BMR and TDEE estimate.
- Jäger R, Kerksick CM, Campbell BI, et al. International Society of Sports Nutrition Position Stand: protein and exercise. J Int Soc Sports Nutr. 2017;14:20. PMID 28642676 · doi:10.1186/s12970-017-0177-8 — protein intake ranges (1.4–2.0 g/kg/day generally; 2.3–3.1 g/kg/day during energy deficit for trained individuals).
- Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (2005) — Acceptable Macronutrient Distribution Ranges: carbohydrate 45–65%, fat 20–35%, protein 10–35% of energy; fiber ≈14 g per 1,000 kcal. National Academies .
The Macro Calculator turns a daily calorie target into a breakdown of protein, carbohydrates, and fat. You enter your stats, activity level, and goal (lose, maintain, or gain), and the tool estimates maintenance calories, adjusts them for the selected goal, and splits the total into gram targets for each macronutrient.
Total calories determine the overall direction of weight change, while the protein, carbohydrate, and fat split describes how those calories are distributed. The tool sets a protein target first, then assigns fat as a share of total calories, and fills the remaining calories with carbohydrates, keeping the split within commonly referenced macronutrient ranges that you can adjust by preference.
How it works (formula)
- BMR is estimated with the Mifflin-St Jeor equation.
- Maintenance (TDEE) = BMR × activity factor.
- Target calories = TDEE × goal multiplier (for example −20% for fat loss, +10% for lean gain), bounded by intake floors.
- Lean body mass = body weight × (1 − body-fat % ÷ 100).
- Protein = lean body mass × a goal-specific value in grams per kg of lean mass.
- Fat = chosen percentage of target calories (typically 25–35%), then ÷ 9 kcal/g for grams.
- Carbohydrates = remaining calories ÷ 4 kcal/g.
Protein here is expressed per kilogram of lean mass . Published guidelines such as the ISSN position stand express protein per kilogram of total body weight (about 1.4–2.0 g/kg/day in general, and 2.3–3.1 g/kg/day during calorie deficits for trained individuals), so the two are not directly interchangeable. The macronutrient percentage ranges align with the Acceptable Macronutrient Distribution Ranges from the Institute of Medicine.
All values are general estimates for informational and educational purposes and will not reflect any individual's exact energy needs or nutritional requirements.