Macronutrients, or “macros”, are the three nutrients that supply your calories: carbohydrates, protein and fat. Once you know your daily calories, this calculator splits them into grams of each macro, per day and per meal.
Calories per gram
| Nutrient | Calories per gram | Main jobs |
|---|---|---|
| Carbohydrates | 4 | Main source of energy, especially for the brain and during exercise |
| Protein | 4 | Builds and repairs muscle and other tissues, makes enzymes and hormones |
| Fat | 9 | Supplies energy, absorbs vitamins A, D, E and K, supports cell membranes |
Recommended ranges
The U.S. National Academies’ acceptable macronutrient distribution ranges for adults are 45 to 65 percent of calories from carbohydrates, 10 to 35 percent from protein and 20 to 35 percent from fat. The presets above sit inside, or close to, these ranges:
- Balanced (50/20/30): a flexible default for most people.
- Higher protein (40/30/30): helpful for fullness, active people and those building muscle.
- Lower carb (25/35/40): some people prefer it for blood-sugar control or appetite. It sits outside the usual carbohydrate range, so discuss it with a professional if you have a medical condition.
- Lower fat (60/20/20): a carbohydrate-focused pattern that suits some endurance athletes.
How to use your macro numbers
- Treat grams as targets to aim for, not a daily pass or fail. Averages across a week matter more than any single day.
- Food quality counts as much as quantity. Choose whole grains, beans, fruit and vegetables, and unsaturated fats such as olive oil, nuts and fish.
- Do not have your calorie number yet? Use the calorie calculator first. Your result is passed to this tool automatically.
- Spread your protein across meals. Our protein calculator shows ranges for different goals.
- Do not forget fiber. See our guide to fiber for easy ways to reach your target.
Frequently asked questions
What are macros?
Macros are short for macronutrients: the carbohydrates, protein and fat in food that provide your calories.
Do I need to track macros?
No. Many people eat well without counting. Tracking can help if you have a specific goal, such as building muscle, or if you want to understand your habits for a short period.
Which macro split is best?
There is no single best split. The best one is nutritionally balanced, fits your preferences and health needs, and is something you can keep doing.
How do I find the grams in my food?
Check the Nutrition Facts label, or look foods up in a database such as USDA FoodData Central. Weighing food gives the most accurate numbers.
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This calculator provides general estimates for healthy adults and is for information only. It is not medical advice and does not replace a conversation with a qualified healthcare professional. Read our disclaimer and editorial policy.