Macro Calculator - Protein, Carbs & Fat

How to use this tool

Enter calorie target. Type your daily calorie goal. Use our BMR/TDEE calculator if you need help finding this number.
Choose a macro preset. Select balanced, low-carb, keto, or high-protein - or choose Custom to enter your own percentages.
Review your macros. Click Calculate macros to see grams and calories from each macronutrient. Rounded gram targets may add up to a few calories more or less than your calorie goal.

What are macronutrients?

Macronutrients (protein, carbohydrates, and fat) are the three food components that supply calories. Protein and carbohydrates each provide 4 kcal/g; fat provides 9 kcal/g. Adjusting your macro ratio while keeping total calories the same affects satiety, energy levels, and body composition outcomes.

Macro split presets

Preset	Protein	Carbs	Fat	Best for
Balanced	30%	40%	30%	General fitness
Low-carb	35%	25%	40%	Fat loss, blood sugar control
Keto	25%	5%	70%	Ketosis, epilepsy management
High-protein	40%	35%	25%	Muscle building, body recomposition

Calorie breakdown per gram

Macronutrient	Calories per gram
Protein	4 kcal/g
Carbohydrates	4 kcal/g
Fat	9 kcal/g
Alcohol (FYI)	7 kcal/g

Sample balanced 2,000 kcal day (30/40/30)

Breakfast: Greek yogurt (protein), oats with berries (carbs), peanut butter (fat)
Lunch: chicken breast + brown rice + olive oil drizzle + salad
Snack: apple + a handful of almonds
Dinner: salmon (protein + fat), roasted sweet potato (carbs), steamed broccoli

These portions aim for about 150 g protein, 200 g carbs, and 67 g fat. Those rounded gram targets calculate to 2,003 kcal, about 3 kcal above the 2,000 kcal target.

Macro presets comparison (2,000 kcal baseline)

Preset	Split (P/C/F)	Protein (g)	Carbs (g)	Fat (g)
Balanced	30/40/30	150	200	67
Low-carb	35/25/40	175	125	89
Keto	25/5/70	125	25	156
High-protein	40/35/25	200	175	56

These percentages match the Macro split presets above. Gram targets are rounded to whole grams, so calories calculated back from the displayed amounts can differ slightly from the 2,000 kcal baseline.

Adjusting macros over time

Static macro targets become less effective as your body adapts - a process called metabolic adaptation. Common adjustment strategies:

Diet breaks: deliberately eating at maintenance for 1–2 weeks after an extended deficit to restore leptin levels and reduce cortisol.
Refeeds: a single day (or weekend) of higher carbohydrate intake mid-cut to support training performance and hormonal balance.
Reverse dieting: gradually increasing calories after a diet by small weekly increments (50–100 kcal) to rebuild metabolic rate without excessive fat regain.

Tracking accuracy

The accuracy of macro tracking depends heavily on measurement method:

Food scale: most accurate method - weighing in grams eliminates the variability of cup measurements (a "cup" of oats can vary by 50+ calories depending on how it's packed).
Restaurant meals: calorie counts can vary ±20–30% from stated values due to portion variation and ingredient substitutions. Treat restaurant tracking as an estimate, not a precise measurement.
Packaged foods: FDA regulations allow ±20% tolerance on Nutrition Facts labels. For most people this is acceptable; competitive athletes may want to weigh even "precisely labeled" foods.

Frequently asked questions

What are macros?

Macros (macronutrients) are the three main nutrient categories that provide calories: protein (4 kcal/g), carbohydrates (4 kcal/g), and fat (9 kcal/g). Tracking macros - rather than just calories - can help you meet protein goals for muscle building or minimize carbs for keto.

How many grams of protein should I eat per day?

General recommendations range from 0.8 g/kg of body weight for sedentary adults (the RDA) to 1.6–2.2 g/kg for those trying to build or preserve muscle. This calculator uses percentage-based splits; for weight-based protein targets, use your body weight and a protein goal first, then back-calculate the calorie contribution.

What is the keto macro split?

A standard ketogenic diet uses roughly 70% of calories from fat, 25% from protein, and 5% from carbohydrates. At 2,000 kcal/day that equates to about 156 g fat, 125 g protein, and 25 g carbs. Keeping carbs under 20–50 g/day typically induces ketosis.

What is a balanced macro split?

A balanced split (30% protein / 40% carbs / 30% fat) is a general-purpose diet that provides adequate protein for many active adults while leaving room for performance carbohydrates. At 2,000 kcal/day: 150 g protein, 200 g carbs, and 67 g fat. Because gram targets are rounded to whole grams, their calculated calories may differ slightly from the calorie target.

Do I need to track macros to lose weight?

No - a calorie deficit drives weight loss regardless of macro split. However, sufficient protein (≥1.6 g/kg) helps preserve muscle during a deficit, and different splits can affect satiety and adherence. Macro tracking is a useful tool but not mandatory.