How macros are calculated
Protein (g) = Calories × Protein % ÷ 4
Carbs (g) = Calories × Carb % ÷ 4
Fat (g) = Calories × Fat % ÷ 9
Carbs (g) = Calories × Carb % ÷ 4
Fat (g) = Calories × Fat % ÷ 9
Example: For 2,200 kcal on a balanced 30/40/30 split: protein = 2,200 × 0.30 ÷ 4 = 165 g, carbs = 2,200 × 0.40 ÷ 4 = 220 g, fat = 2,200 × 0.30 ÷ 9 = 73 g. Across three meals that is about 55 g protein, 73 g carbs and 24 g fat per meal.
Choosing a split
- Balanced suits most people and falls within the U.S. Dietary Guidelines ranges (10–35% protein, 45–65% carbs, 20–35% fat are the official ranges; 30/40/30 is a popular fitness variant).
- High protein helps when cutting calories or building muscle.
- Low carb may help appetite control for some people and suits those who prefer fewer starches.
- Keto keeps carbohydrates very low (usually under 50 g a day) to induce ketosis; talk to a doctor first if you have a medical condition.
- Endurance provides the carbohydrate that runners, cyclists and other endurance athletes need for long training sessions.
How to use the calculator
- Enter your daily calorie target, or estimate it first with the calorie calculator.
- Choose a macro split, or set your own percentages for protein, carbohydrates and fat (they must add up to 100%).
- Read grams per day and per meal for each macronutrient.
Macros at different calorie levels (30/40/30)
| Calories | Protein (30%) | Carbs (40%) | Fat (30%) |
|---|---|---|---|
| 1,600 | 120 g | 160 g | 53 g |
| 1,800 | 135 g | 180 g | 60 g |
| 2,000 | 150 g | 200 g | 67 g |
| 2,200 | 165 g | 220 g | 73 g |
| 2,500 | 188 g | 250 g | 83 g |
| 2,800 | 210 g | 280 g | 93 g |
Official ranges
The U.S. National Academies’ Acceptable Macronutrient Distribution Ranges (AMDR) for adults are:
- Protein: 10–35% of calories (the RDA minimum is 0.8 g per kg of body weight a day).
- Carbohydrates: 45–65% of calories.
- Fat: 20–35% of calories, with saturated fat under 10%.
Popular splits for fitness, like 30/40/30, are higher in protein and lower in carbs than these ranges but still within healthy limits for most people. Very low-carb (keto) diets fall outside the AMDR and are best discussed with a health professional, especially if you have a medical condition or take medication.
How much protein?
Research on active people, summarized by the International Society of Sports Nutrition, supports about 1.4–2.0 g of protein per kg of body weight a day to build and maintain muscle — roughly 0.6–0.9 g per pound. During weight loss, higher protein (toward the top of that range) helps preserve muscle and keeps you fuller. Spread it across meals: 20–40 g per meal is a practical target.
Tracking tips
- Weigh foods for the first couple of weeks; portion estimates are often 20–50% off.
- Hit protein and calories first; the exact carb/fat balance matters less for most goals.
- Prefer fiber-rich carbs (vegetables, fruit, legumes, whole grains) and unsaturated fats (olive oil, nuts, fish).
- Alcohol provides 7 kcal per gram and counts toward calories but isn’t a macronutrient you need.
- Reassess every 4–6 weeks based on weight, energy, training and how you feel.
Frequently asked questions
What are macros?
Macronutrients are the three nutrients that provide calories: protein and carbohydrates (4 kcal per gram each) and fat (9 kcal per gram). Alcohol also provides 7 kcal per gram but is not a nutrient you need.
How much protein do I need?
The RDA is 0.8 g per kg of body weight for sedentary adults. People who strength-train or are losing weight often benefit from about 1.6–2.2 g/kg. If your result from a percentage split is lower than that, choose the high-protein option.
Which macro split is best for weight loss?
Total calories matter most for weight loss. Within that, higher protein helps preserve muscle and keeps you fuller. The best split is the one you can stick to consistently.
Where do I get my calorie target?
Use the calorie calculator to estimate your daily needs for maintaining, losing or gaining weight, then enter that number here.
How many calories are in a gram of each macro?
Protein 4 kcal, carbohydrates 4 kcal, fat 9 kcal and alcohol 7 kcal per gram.
Do I count fiber as a carbohydrate?
Food labels include fiber in total carbohydrates. Some people track “net carbs” (total minus fiber), but for calorie targets it’s simplest to count total carbs.