Macro Calculator
Split your daily calories into grams of protein, carbs, and fat using adjustable macronutrient percentages.
- Carbohydrates
- 200 g/day
- Fat
- 67 g/day
- Percentages total
- 100%
Formula: Grams = calories × % ÷ 100 ÷ (4 kcal/g protein & carbs, 9 kcal/g fat)
About Macro Calculator
Macro Calculator is a free online calculator that gives you an instant, accurate result as you type. Split your daily calories into grams of protein, carbs, and fat using adjustable macronutrient percentages.
The calculation uses the standard formula Grams = calories × % ÷ 100 ÷ (4 kcal/g protein & carbs, 9 kcal/g fat) and updates live with every change to the inputs. Everything runs client-side in your browser — fast, private, and free to use as often as you like.
Protein and carbohydrate provide about 4 kcal per gram while fat provides about 9 kcal per gram, which is why fat grams come out lower for the same percentage.
Results are estimates for educational purposes and not medical advice.
Frequently Asked Questions
Is Macro Calculator free to use?
Yes. Macro Calculator is completely free, with no sign-up, no downloads, and no usage limits. You can use it as many times as you like on any device with a web browser.
How accurate is this calculator?
The calculator applies the standard formula (Grams = calories × % ÷ 100 ÷ (4 kcal/g protein & carbs, 9 kcal/g fat)) with full floating-point precision and rounds only the displayed result. For most practical purposes the results are exact.
What macro split should I use?
A 40/30/30 carb/protein/fat split is a common balanced starting point; endurance athletes often raise carbs while low-carb diets shift calories toward fat.
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