Quick answer: Macros turn a calorie target into grams. Protein and carbohydrates give 4 calories per gram and fat gives 9. On 2,000 calories a day a balanced 30% protein, 40% carbohydrate and 30% fat split is 150 g of protein, 200 g of carbohydrates and 67 g of fat.
Calories tell you how much to eat, and macros describe what that food is made of: protein, carbohydrates and fat. Many people track macros to build muscle, lose fat, or follow a specific way of eating.
If you do not yet know your daily calories, use the calorie calculator first, then enter the result here. Choose a ready-made split or set your own, and the calculator converts the percentages to grams you can aim for each day.
From percentages to grams
Each macro provides a fixed amount of energy per gram, so the conversion is simple:
Carbohydrates: 4 kcal per gram
Fat: 9 kcal per gram
Grams = calories × share of calories ÷ kcal per gram
There is no single best split. Higher protein helps some people feel full and hold onto muscle while losing weight. Lower carbohydrate plans suit some people and not others. Very low-calorie or very low-carbohydrate plans, and any plan for people with medical conditions, should be planned with a doctor or dietitian.
A worked example
Example. On 2,000 calories a day with a balanced split of 30% protein, 40% carbs and 30% fat: protein is 600 kcal ÷ 4 = 150 g, carbs are 800 kcal ÷ 4 = 200 g and fat is 600 kcal ÷ 9 = about 67 g.
Popular splits on 2,000 calories
| Split (protein / carbs / fat) | Protein | Carbs | Fat |
|---|---|---|---|
| Balanced 30 / 40 / 30 | 150 g | 200 g | 67 g |
| High protein 40 / 30 / 30 | 200 g | 150 g | 67 g |
| Lower carb 30 / 20 / 50 | 150 g | 100 g | 111 g |
| Keto 20 / 5 / 75 | 100 g | 25 g | 167 g |
Grams for a 2,000-calorie day. For comparison, the U.S. Dietary Guidelines list acceptable ranges for adults of 10 to 35% of calories from protein, 45 to 65% from carbohydrates and 20 to 35% from fat.
Common mistakes to avoid
- Copying someone else’s split. The best split is one you can keep to, and it depends on your goal, appetite, training and health.
- Forgetting that fat has more than twice the calories per gram. Small changes in fat grams move the calorie total quickly.
- Setting a very low carbohydrate or very low calorie plan without advice. People with medical conditions or who take medication should speak to a doctor or dietitian first.
Frequently asked questions
How many grams of protein do I need?
General guidance for healthy adults is at least 0.8 g per kg of body weight a day, and active people or those losing weight often aim higher, around 1.2 to 2 g per kg. Your doctor or dietitian can advise on what suits you.
What macro split should I choose?
Start with the balanced split if you are unsure, and adjust based on how you feel and your results. The best split is one you can keep up.
Do I have to hit the numbers exactly?
No. Food tracking is approximate. Aim to be close on most days rather than perfect every day.
Where do I get my daily calorie number?
Use the calorie calculator on this site to estimate your maintenance calories, then subtract for weight loss or add for weight gain.
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Sources and further reading
- Macronutrient (Wikipedia)
- Dietary Guidelines for Americans (U.S. Department of Agriculture and HHS)
- Basal metabolic rate, including the Mifflin-St Jeor equation (Wikipedia)
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