Macro calculator
A calorie target tells you how much to eat; your macros tell you what those calories are made of. This free calculator splits any daily calorie target into grams of protein, carbohydrate, and fat using three proven ratios — balanced, high-protein, and low-carb. Enter your target calories, pick a split, and see your grams update instantly, with no account or email. Because protein and carbs carry about 4 calories per gram and fat about 9, the same calorie total lands on very different gram amounts depending on the ratio you choose. Not sure of your calorie number yet? Estimate maintenance with our TDEE calculator or set a weight-loss target with the deficit calculator, then bring that figure back here.
Protein
150 g
30% · 600 kcal
Carbs
200 g
40% · 800 kcal
Fat
67 g
30% · 603 kcal
How the macro calculation works
Every macro split starts from your calorie target and a set of percentages that add up to 100%. Each percentage is the share of your calories that comes from that macro. This calculator offers three ratios, written as protein / carbs / fat:
- Balanced — 30 / 40 / 30. An even spread that works for most goals.
- High-protein — 40 / 30 / 30. More protein to protect muscle when dieting or training.
- Low-carb — 35 / 25 / 40. Fewer carbs, more energy from fat.
To turn a percentage into grams we take that share of your calories and divide by the calories each macro holds — 4 kcal per gram for protein and carbohydrate, 9 kcal per gram for fat:
grams = (calories × macro%) ÷ kcal-per-gram
protein & carbs ÷ 4 · fat ÷ 9
For example, on a 2,000-calorie balanced split, protein is 30% of 2,000 = 600 kcal ÷ 4 = 150 g; carbs are 40% = 800 kcal ÷ 4 = 200 g; fat is 30% = 600 kcal ÷ 9 ≈ 67 g. Grams are rounded to whole numbers, so the calories add back to within a few of your target. Ratios are a helpful frame, not a rule — the number that matters most for most goals is hitting your calories and enough protein.
Frequently asked questions
What are macros?
Macros — short for macronutrients — are the three nutrients that supply calories: protein, carbohydrates, and fat. Protein and carbs provide about 4 calories per gram, fat about 9. Splitting your calorie target across the three lets you plan meals with a specific balance rather than just a calorie number.
Which macro split should I choose?
Balanced (30% protein / 40% carbs / 30% fat) suits most people and most goals. High-protein (40/30/30) helps preserve muscle when losing weight or training hard. Low-carb (35/25/40) shifts energy toward fat and suits people who prefer fewer carbs. There is no single best split — pick what fits your food preferences and how you feel.
How do I find my calorie target?
Start with your maintenance calories (TDEE), then adjust for your goal. Our free TDEE calculator estimates maintenance from your body stats, and the calorie deficit calculator helps you set a target for weight loss. Enter that number here to get your grams.
Estimate a real plate instead
Numbers are a start — logging is where progress happens. Snap a photo of your meal and NibbleCal estimates the calories and macros in about 3 seconds.
Try it with a photo — free, no signup