Building your own macro split
Once you know your daily calorie target — from the Calories or TDEE calculator, or from a coach — the next decision is how to split it between protein, carbohydrates and fat. Unlike the fixed 30/40/30 split used on the Calories Calculator, this tool lets you set your own ratio and see exactly how many grams of each macronutrient that works out to.
A few common starting points
A balanced split (roughly 30% protein, 40% carbs, 30% fat) suits most general fitness goals. A higher-protein, lower-carb split (35-40% protein, 25-30% carbs) is common during fat-loss phases to support satiety and muscle preservation. Endurance athletes often run higher carbohydrate percentages (45-55%) to fuel training volume. None of these is objectively "correct" — they're starting points to adjust based on how you perform and feel.
Set protein first
Of the three macronutrients, protein is the one worth fixing first and treating as closest to non-negotiable, since it's most directly tied to muscle preservation and satiety. Once protein is set, the carb-to-fat balance is largely a matter of personal preference and how your body responds — some people perform and feel better on relatively higher carbs, others on relatively higher fat, with total calories and protein held constant.