Macro Calculator
Split your daily calories into grams of carbs, protein, and fat.
Runs in your browser — nothing is sent or saved.
How to use the macro calculator
- Enter your daily calorie target.
- Choose a macro split, or pick Custom and set your own percentages.
- Read the grams of carbs, protein, and fat.
- Copy the link to save or share the plan.
What macros are
Macros, short for macronutrients, are the three nutrients that carry calories: protein, carbs, fat. Getting the balance of protein carbs fat right shapes your results. Counting macros means hitting daily gram targets for each, not just a calorie total, which is the idea behind IIFYM (if it fits your macros). This macronutrient calculator turns a calorie goal into those gram targets using a ratio you choose.
The calorie value of each macro
The grams come straight from how many calories each macro holds.
| Macro | Calories per gram |
|---|---|
| Carbohydrate | 4 |
| Protein | 4 |
| Fat | 9 |
So on a 2,000 calorie day, a 40/30/30 split gives 800 calories of carbs (200 g), 600 of protein (150 g), and 600 of fat (about 67 g).
Common macro splits
There is no single correct ratio. These are popular starting points.
| Split | Carbs | Protein | Fat | Often used for |
|---|---|---|---|---|
| Balanced | 40% | 30% | 30% | general eating |
| Low carb | 25% | 35% | 40% | fat loss, appetite control |
| High protein | 30% | 40% | 30% | building or keeping muscle |
| Keto | 5% | 25% | 70% | ketogenic diets |
Pick the one that suits your goal, or use Custom to match a plan you already follow. The three percentages must total 100.
Getting your calorie number first
Macros only make sense once you have a calorie target. If you do not have one, work out your maintenance calories with the calorie calculator, adjust for a loss or gain goal, then bring that number here to split it. Protein is worth setting first, since it protects muscle when you are eating in a deficit.
An estimate, not medical advice
These ratios are general guidance, not a prescription. The right split depends on your goals, training, and any health conditions. Speak to a dietitian for a plan built for you.
FAQ
How do I calculate my macros?
Enter your daily calorie target and choose a split. The tool multiplies the calories by each percentage, then divides by 4 for carbs and protein and by 9 for fat to get the grams.
What are the best macros for weight loss?
For macros for weight loss, many people do well on a higher-protein, moderate-carb split while in a calorie deficit, because protein preserves muscle and keeps you full. There is no single best ratio, so match it to your goal.
Do macros matter more than calories?
Calories decide weight change; macros shape body composition and how you feel. Hitting your calorie target with enough protein is the combination most plans aim for.
Can I set my own ratio?
Yes. Choose Custom and enter your own carbs, protein, and fat percentages. They need to add up to 100%.
Is my information private?
Yes. Everything is calculated in your browser and nothing you enter is uploaded or saved.