Macro calculator
Daily protein, carbs and fat in grams for your calorie goal.
About this calculator
This macro calculator turns your calorie needs into daily targets for protein, carbohydrates and fat. Choose your goal, lose weight, maintain or build muscle, and a diet style that suits you.
Your macros are shown in grams per day and per meal, ready to use with a food tracking app.
How it works
Works out your TDEE with the Mifflin-St Jeor equation, adjusts it for your goal, then splits the calories by your diet. Protein and carbs have 4 kcal per gram and fat has 9.
Last reviewed:
Worked example
- Units: Feet and pounds
- Sex: Female
- Age: 35 years
- Height: 5 ft 7 in
- Weight: 155 lb
- Activity: Light exercise, 1 to 3 days a week
- Goal: Maintain
- Diet: Balanced: 25% protein, 50% carbs, 25% fat
- Meals a day: 3
Daily calories: 1,967 kcal (your TDEE)
Common questions
What are macros?
Macronutrients, or macros, are the three nutrients that provide calories: protein, carbohydrates and fat. Counting them helps you hit a calorie goal while getting enough protein.
How much protein do I need?
Many adults do well on 1.2 to 2 g of protein per kg of body weight a day, at the upper end if you train hard or are losing weight. The calculator shows your figure per kg.
Is a keto diet better for weight loss?
Weight loss mostly comes down to calories. Keto suits some people, but the best split is one you can keep to and that gives you enough protein.
Sources and further reading
The story behind it
Where the idea came from: The 4-4-9 calorie values for protein, carbohydrate and fat come from Wilbur Atwater's experiments in the late 1800s.
Atwater, an American chemist, burned foods and measured what people ate and excreted to work out how much energy each nutrient really provides. His averages of 4, 4 and 9 kcal per gram are still printed on food labels today. Counting macros, popular with athletes since the 2000s, rests on the same numbers.
Why you can trust this calculator
- It runs in your browser. Nothing you type into it is sent anywhere.
- The method is explained on this page, so you can check it yourself.
- Free to use, with no sign-up.
- Results are estimates, not medical advice.
- Spotted a mistake? Tell us and we'll look into it.
After 15 years as a mathematics educator, I built CalculStore to give students, teachers, professionals and anyone working with numbers simple, reliable tools.
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