Macro Calculator
Turn a calorie target into protein, carb, and fat gram targets.
What Are Macros & Why They Matter
Macronutrients — protein, carbohydrates, and fat — are
the three nutrients that supply your body with energy (unlike micronutrients like vitamins and
minerals, which don't provide calories). Protein and carbohydrate each provide about 4 calories per
gram, while fat provides about 9 — more than double — which is why fat-heavy foods pack more calories
into a smaller volume.
Protein supplies the amino acids your body uses to repair and build muscle tissue, and
is the macro most linked to preserving lean mass while eating in a calorie deficit. It's also the most
satiating macro gram-for-gram and has the highest thermic effect of food, meaning your body burns more
calories digesting it than it does digesting carbs or fat.
Carbohydrates are your body's preferred fuel for the brain and for higher-intensity
exercise, and getting enough supports training performance and recovery. Whole-food sources — vegetables,
fruit, whole grains, legumes — also supply fiber, which supports digestion and satiety.
Fat is required for hormone production (including sex hormones), supports cell membrane
structure, and is necessary to absorb the fat-soluble vitamins A, D, E, and K. Going too low on fat for
extended periods can disrupt hormone levels.
Total calories are still what determines whether you lose, maintain, or gain weight — a macro split
doesn't override that. What it changes is body composition, hunger, energy levels, and how sustainable a
calorie target feels day to day, which is why picking a split you can actually stick with matters as
much as the exact percentages. For context, the Institute of Medicine's Acceptable Macronutrient
Distribution Ranges (AMDR) suggest adults get roughly 10–35% of calories from protein, 45–65% from
carbohydrate, and 20–35% from fat — the four presets above sit within or near that range, just shifted
toward different priorities.
Read the report →