Macro
calculator
Calories set the size of the day; macros set its shape. Enter your target and a split, and get the actual grams of protein, carbs and fat to aim for.
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From calories to a plate
Each macronutrient carries a fixed energy density, protein and carbs about 4 kcal per gram, fat about 9. Split your calorie target by percentages, divide by those densities, and the day becomes concrete grams.
Carbs: 2400×0.40÷4 = 240 g · Fat: 2400×0.30÷9 = 80 g
Choosing a split
Evidence supports a wide range of splits, adherence matters more than the exact ratio. The anchor most plans agree on is protein: roughly 1.6–2.2 g per kilogram of body weight when training or dieting, which preserves muscle in a deficit. Set protein first, then divide the remainder between carbs and fat by preference, carbs fuel hard training; fat supports hormones and satiety (don't go below ~20% for long).
Get the calorie target itself from the TDEE calculator, and the resting baseline from BMR.
Macros FAQ
Multiply calories by each macro's percentage, then divide by its energy density: 4 kcal/g for protein and carbs, 9 kcal/g for fat. A 2,400 kcal day at 30/40/30 gives 180 g protein, 240 g carbs, 80 g fat.
Common evidence-based guidance for people training or dieting is roughly 1.6–2.2 g per kg of body weight daily. Sedentary minimums are lower (about 0.8 g/kg), but higher intakes help preserve muscle in a deficit.
Research consistently finds that with calories and protein matched, low-carb and higher-carb diets produce similar fat loss. Pick the split you can sustain, adherence beats ratio.
Here, no, the calculator normalizes whatever you enter. In practice treat grams as daily targets to land near, not laws; ±10 g is noise.