Macro Calculator
Split daily calories into protein, carbs and fat in grams
100% free. Runs entirely in your browser - your files and data never leave your device and nothing is uploaded to any server.
Split
Percentages should add to 100. Protein and carbs are 4 kcal/g; fat is 9 kcal/g.
Estimates only. Not medical advice and not a diagnosis. Talk to a clinician about your own numbers. Pair this with the calorie calculator if you do not know your daily target.
About this tool
Macros are the grams of protein, carbohydrate and fat that add up to a calorie target. Protein and carbs are 4 kcal per gram; fat is 9. Presets cover a balanced split, higher protein, lower carb and an endurance bias. You can type your own percentages. They should add to 100, otherwise the grams will not match the calorie target. Pair this with the calorie calculator if you do not yet have a daily kcal number. Estimates only. Not medical advice.
How to use this tool
- Enter daily caloriesUse your TDEE target, not a random 2,000 unless that happens to fit.
- Pick a split or type percentagesBalanced is 30/40/30. High protein is 40/35/25. They should add to 100.
- Use the grams in a food logWeighing food still beats an app's generic entries when you care about the last 10 grams of protein.
How to calculate your macros
Multiply your calorie target by the percentage for each macro, then divide by its calories per gram: 4 for protein and carbohydrate, 9 for fat. On 2,000 calories with a 30/40/30 split, protein is 600 calories / 4 = 150 g, carbohydrate 800 / 4 = 200 g, and fat 600 / 9 = about 67 g.
The percentages must add up to 100, otherwise the grams will not match the calorie target. For protein, many active adults aim for about 1.6 g per kilogram of body weight, which for a 75 kg person is about 120 g a day.
Key features
- Grams and kcal for protein, carbs and fat from one calorie number.
- Four presets plus custom percentages.
- Live total so you can see if the split still adds to 100.
- Private in your browser.
Common uses
- Turning a TDEE target into a grocery-level gram split.
- Raising protein without guessing the remaining carbs and fat.
- An endurance day that wants more carbohydrate.
- Checking an app's "40/30/30" against actual grams.
Tips for better results
- If percentages do not equal 100, fix them before you log food.
- Many active adults land near 1.6 g protein per kg of body weight. Convert if you prefer grams per kilogram to percentages.
- Fat grams look small because each gram is 9 kcal.
- Re-run after you change the calorie target, not only the split.
Mistakes to avoid
- Using 2,000 kcal because a label said so, when your TDEE is 1,600 or 2,800.
- Treating the lower-carb preset as a clinical ketogenic diet.
- Chasing exact grams every day. A weekly average is what body composition follows.
- Ignoring fibre, micronutrients and food quality once the macros "fit".
Frequently asked questions
Many active adults land near 1.6 g per kg of body weight. This page works in calorie percentages; convert if you prefer grams per kilogram.
Yes for a clean split. If they do not, the grams still compute from each percentage independently, so the calories will not match the target.
The lower-carb preset is not a clinical ketogenic diet. Very low carbohydrate eating needs a clinician if you take diabetes medication.
Protein kcal / 4, carb kcal / 4, fat kcal / 9. That is the Atwater convention used on most food labels.
Spread it over the day: 25-40 g per meal from foods such as eggs, Greek yoghurt, chicken, fish, tofu, lentils or cottage cheese. Planning the protein for each meal first makes the carbs and fat easier to fit around it.
On nutrition labels in the US, fibre is included in total carbohydrate; in the UK and EU it is listed separately. Track whichever your labels show, consistently - mixing the two systems makes the totals drift.
They can. Some people eat more carbs on training days and fewer on rest days while keeping protein steady. If that feels complicated, keeping the same targets every day works fine for most goals.