Macro Calculator — Step-by-Step Solutions

The Macro Calculator determines your ideal daily intake of protein, carbohydrates, and fat based on your calorie goals. It supports four modes: macros by goal (weight loss, maintenance, muscle gain), custom ratio entry, grams from calories, and per-meal macro split.

Enter your daily calorie target and the calculator will show recommended grams and percentages for each macronutrient. Pairs with our Calorie and TDEE calculators for complete nutrition planning.

Total Daily Calories (kcal)

Goal

Your calculations will appear here

How to Use the Macro Calculator

Enter your total daily calories. If you do not know them, work them out first with the TDEE or Calorie Calculator.
By Goal: choose Cut, Maintain or Bulk to use a preset split. Custom Ratio: set your own protein, carbohydrate and fat percentages, which must add up to 100; the running total is shown under the fields.
Grams from Calories shows how many grams of each nutrient it would take to supply the whole calorie amount from that nutrient alone, a quick conversion check. Per-Meal Split takes the grams for the selected goal and divides them across 1 to 10 meals.
Results are planning figures, not medical or nutrition advice. Speak to a registered dietitian for a personal plan, especially if you have a health condition.

Formula and Theory

Macronutrients are the three nutrients that supply energy: protein and carbohydrate at 4 kilocalories per gram, and fat at 9 kilocalories per gram. A macro split states what share of your daily calories comes from each, and converting percentages into grams is simple arithmetic.

For each nutrient, grams = calories x percentage / calories per gram. With 2,000 kcal and 30% fat, fat calories are 600 and fat grams are 600 / 9 = 66.7. The same calories give far fewer grams of fat than carbohydrate because fat is more than twice as energy-dense.

The presets in this tool are Cut and Maintain at 40% protein, 30% carbohydrate and 30% fat, and Bulk at 30% protein, 40% carbohydrate and 30% fat. They are starting points, not recommendations; reasonable splits depend on health, training and preferences. Check the totals add back to your calories, within a few kilocalories of rounding.

Worked Examples

Example 1: Maintain preset at 2,000 kcal

Problem: Split 2,000 kcal as 40% protein, 30% carbohydrate and 30% fat.

Solution: Protein: 2,000 x 0.40 = 800 kcal, 800 / 4 = 200 g. Carbohydrate: 2,000 x 0.30 = 600 kcal, 600 / 4 = 150 g. Fat: 600 kcal, 600 / 9 = 66.7 g, shown as 67 g.

Answer: Protein 200 g, carbohydrate 150 g, fat 67 g

Example 2: Bulk preset at 2,000 kcal

Problem: Use the 30% protein, 40% carbohydrate, 30% fat split on 2,000 kcal.

Solution: Protein: 600 kcal / 4 = 150 g. Carbohydrate: 800 kcal / 4 = 200 g. Fat: 600 kcal / 9 = 66.7 g.

Answer: Protein 150 g, carbohydrate 200 g, fat 67 g

Example 3: Custom ratio

Problem: Split 2,500 kcal as 30% protein, 45% carbohydrate and 25% fat.

Solution: Protein: 2,500 x 0.30 = 750 kcal, 750 / 4 = 187.5 g. Carbohydrate: 2,500 x 0.45 = 1,125 kcal, 1,125 / 4 = 281.25 g. Fat: 2,500 x 0.25 = 625 kcal, 625 / 9 = 69.4 g.

Answer: Protein 188 g, carbohydrate 281 g, fat 69 g (rounded)

Example 4: Per-meal split

Problem: Divide the 2,000 kcal maintain plan over 3 meals.

Solution: Daily totals are 200 g protein, 150 g carbohydrate and 66.7 g fat, and 2,000 kcal. Divide by 3: protein 66.7 g, carbohydrate 50 g, fat 22.2 g, calories 666.7. The tool rounds each daily figure first (fat shows as 67), then divides.

Answer: About 67 g protein, 50 g carbohydrate, 22 g fat and 667 kcal per meal

Frequently Asked Questions

How do I calculate macros?

Pick your daily calories and a percentage split, then divide each nutrient calories by its calories per gram: 4 for protein and carbohydrate, 9 for fat.

What macro split is best?

There is no single best split. It depends on your health, training and preferences. The presets here are starting points; a registered dietitian can tailor a plan to you.

Why does fat give fewer grams for the same percentage?

Fat has 9 kcal per gram against 4 for protein and carbohydrate. The same 600 kcal is 150 g of carbohydrate but only about 67 g of fat.

What if my percentages do not add up to 100?

The tool shows the running total and flags it when it is not 100. Grams are worked out from the percentages exactly as entered, so a total above or below 100 will not add back to your calorie figure. Adjust the three values until they total 100.

Do macros need to match the calorie total exactly?

They match within a few kilocalories. Rounding grams to whole numbers causes small differences, and food labels themselves are approximate.

Where does my calorie figure come from?

Use your estimated maintenance calories from the TDEE Calculator, then adjust for your goal. All of these numbers are estimates and not medical advice.