Macro Calculator — Turn a Calorie Target into Grams of Protein, Carbs and Fat

How to use the macro calculator

1. Enter your Daily calorie target in kcal.
2. Choose a Macro split (protein / carbs / fat): Balanced 30 / 40 / 30, High protein 40 / 30 / 30, Lower carb 35 / 25 / 40, Endurance 20 / 55 / 25, Ketogenic 20 / 5 / 75, or Custom.
3. For Custom, enter Protein, Carbohydrate and Fat percentages that add up to 100.
4. Set Meals per day.
5. Read the grams per day, then check the table for calories and grams per meal. The donut chart shows the calorie split.

What it does and when to use it

A calorie target tells you how much to eat. A macro target tells you what to eat it as. Many people find grams easier to plan with than percentages, because food labels list grams.

Use the calculator to:

• Turn a calorie goal into a simple daily target for each macronutrient.
• Plan meals by splitting the daily grams across the meals you eat.
• Compare how different splits change your protein, carbohydrate and fat.
• Check that a custom split adds up before you build a meal plan around it.

Start with a calorie target from the TDEE Calculator. If you mainly care about protein, the Protein Intake Calculator bases its range on body weight instead. To check your weight for your height, see the BMI Calculator.

How it works

For a calorie target K and percentages p, c and f:

• Protein grams = K × p ÷ 100 ÷ 4
• Carbohydrate grams = K × c ÷ 100 ÷ 4
• Fat grams = K × f ÷ 100 ÷ 9
• Grams per meal = grams per day ÷ meals per day

The energy values of 4, 4 and 9 kcal per gram are the general Atwater factors. The FAO gives them as 4.0 kcal/g for protein and carbohydrate and 9.0 kcal/g for fat. If the three percentages do not add up to 100, the tool asks you to fix them instead of guessing. Everything runs in your browser.

Worked examples

A 2,000 kcal balanced plan (30 / 40 / 30) over 3 meals.

So Protein: 150 g and Fat: 66.67 g each day.

A 1,800 kcal custom plan (40 / 30 / 30) over 4 meals. That gives 180 g of protein, 135 g of carbohydrate and 60 g of fat a day, or 45 g, 33.8 g and 15 g per meal.

A split that does not add up. 30 / 40 / 25 totals 95%, so the tool shows The percentages add up to 95% and asks for a total of 100%.

Limits and tips

• The presets are common patterns, not recommendations for you.
• The Atwater factors are averages. The energy you absorb from a specific food can differ a little.
• Very low carbohydrate diets such as the ketogenic preset are not suitable for everyone. Get medical advice first if you take medication or have a health condition.