Macro Calculator: Protein, Carbs and Fat
Macros — short for macronutrients — are the three nutrients that provide your calories: protein, carbohydrates and fat. Hitting the right mix makes dieting easier: enough protein keeps your muscle full, carbs fuel your training and fat keeps your hormones running. This free macro calculator turns your daily calorie target into gram targets for cutting, maintaining or bulking, and shows you every step of the math.
Macro Calculator
How to Use This Macro Calculator
Pick your goal — cut, maintain or bulk — and enter your total daily calories. If you do not know that number, get it first from the TDEE Calculator (for maintenance) or the Calorie Calculator (for a lose or gain target).
Click Calculate and you will see gram targets for protein, carbs and fat, with the calories each contributes and the percentage split behind them.
The ratios shift with your goal: cutting leans on protein to protect muscle, bulking adds carbs to fuel training, and maintaining sits in between. Recalculate whenever your calorie target changes.
The Formula
Each macro has a fixed energy density: protein and carbs supply 4 calories per gram, while fat supplies 9. So the plan is simple: grams = calories × percent ÷ calories-per-gram.
The split depends on your goal — Cut: 40% protein, 30% carbs, 30% fat. Maintain: 30% protein, 40% carbs, 30% fat. Bulk: 30% protein, 45% carbs, 25% fat.
Worked example: maintaining on 2,000 calories — protein 2,000 × 0.30 ÷ 4 = 150 g; carbs 2,000 × 0.40 ÷ 4 = 200 g; fat 2,000 × 0.30 ÷ 9 = 66.7 ≈ 67 g. Check the arithmetic: 150 × 4 + 200 × 4 + 67 × 9 = 600 + 800 + 603 = 2,003 — the rounding costs one gram of fat and about 3 calories.
Tips for Hitting Your Macros
Treat protein as a minimum, not an exact target — about 1.2–2.2 g per kg of body weight depending on your goal. Check your number against the Protein Calculator and build the rest of the plan around it.
Carbs are not the enemy. Around your workouts and on training days, they fuel performance; eating them mostly from whole sources — oats, rice, potatoes, fruit — keeps energy stable and hunger low.
You do not need to hit all three grams to the last gram. A 5–10% wobble from day to day makes no difference; what matters is the average across a week, and that your total calories land where the plan puts them.
Frequently Asked Questions
What are macros and why do they matter?
Macronutrients are protein, carbohydrates and fat — the three nutrients that supply calories (4, 4 and 9 calories per gram). They matter because they are not interchangeable: protein protects muscle and keeps you full, carbs fuel performance and fat supports hormones. Counting macros is a way of managing both calories and the quality of your diet.
How much protein do I need per day?
For most active people, 1.2 to 2.2 grams per kilogram of body weight (about 0.55–1.0 g per lb). The lower end suits maintenance, the upper end suits cutting or muscle building. Our Cut and Bulk ratios are built to land in this range for typical calorie intakes.
Do macro ratios matter for weight loss?
Calories decide whether you lose weight; macros decide what you lose and how you feel. Keeping protein high while cutting preserves muscle, and fiber-rich carbs help with satiety. The specific fat-to-carb split is flexible — pick the one you can sustain.
What are good sources of carbs and fat?
Whole carbs: oats, rice, quinoa, potatoes, beans, fruit and vegetables. Healthy fats: olive oil, avocado, nuts and seeds, eggs, and fatty fish like salmon. Pair these with lean proteins — chicken, fish, eggs, Greek yogurt, tofu — and you have most of a good plan.
Should I track macros or just calories?
Both work; which you choose depends on your goal. If you just want to lose weight, calories alone are enough. If you train seriously, or if you struggle with hunger while cutting, tracking macros — especially protein — gives you a more reliable plan for about the same effort.