Number Macro Calculator
Calories set the budget; macros decide what the budget buys. Enter a daily calorie target — or build one from your stats — then pick a split and get exact grams of protein, carbs and fat to aim at.
How it works
In TDEE mode, BMR comes from the Mifflin–St Jeor equation (men: 10 × kg + 6.25 × cm − 5 × age + 5; women the same with −161), multiplied by your activity factor, then adjusted by your goal. The split then divides the calories: each macro’s share ÷ 4 kcal/g for protein and carbs, ÷ 9 kcal/g for fat. Note the percentages are of calories, not grams — 30% fat by calories is far fewer grams than 30% protein.
Formula & worked example
Formula: Grams = calories × split % ÷ energy density: protein and carbs carry 4 kcal per gram, fat 9 kcal per gram. In TDEE mode the calorie target comes from the Mifflin–St Jeor BMR — men: 10 × kg + 6.25 × cm − 5 × age + 5; women: the same with −161 — multiplied by the activity factor and adjusted by the goal.
Worked example: At 2,000 kcal, the balanced split (30/40/30) gives 150 g protein, 200 g carbs and 66.7 g fat; high-protein (40/30/30) gives 200/150/66.7; low-carb (35/20/45) 175/100/100; keto (20/5/75) 100/25/166.7. A 30-year-old man at 80 kg and 178 cm has a BMR of 1,767.5 kcal, a TDEE of about 2,740 at moderate activity.
When to use this
- You have a calorie target and need it turned into grams you can actually shop and cook to.
- You are trying keto and need the carb ceiling in grams, not a percentage you have to convert at the supermarket.
- You train and want to check that your protein target survives your calorie cut.
- Your calories are coming from an app or a guess and you want a target built from your own stats instead.
How to use it, step by step
- Either type a calorie target you already trust, or switch to the stats mode and build one from sex, age, weight, height and activity.
- In stats mode, add the goal adjustment — the maintain, slow-loss and gain steps are built in.
- Pick the split that matches how you intend to eat: balanced, high-protein, low-carb or keto.
- Read protein, carbs and fat in grams per day, and note the percentages are shares of calories, not of grams.
- Re-run it whenever the calorie target changes; the grams move with the budget.
What the inputs mean
| Input | What it is | Typical values |
|---|---|---|
| Daily calories | The budget the split divides, typed in directly or built in stats mode | Commonly 1,500 to 3,000 kcal |
| Activity level | Multiplier over BMR in stats mode | 1.2 sedentary to 1.9 athlete |
| Goal adjustment | Calories added or removed from maintenance in stats mode | Maintain, plus or minus 250, plus or minus 500 |
| Macro split | Protein, carb and fat shares of calories | Balanced 30/40/30, high-protein 40/30/30, low-carb 35/20/45, keto 20/5/75 |
Another worked example
Built from stats rather than a typed-in number: a 32-year-old woman, 68 kg and 170 cm, lightly active, with the goal set to lose slowly. Her BMR is 1,422 kcal, her TDEE before the goal adjustment is 1,955 kcal, and the slow-loss step sets the target at 1,705 kcal. On the low-carb preset (35% protein, 20% carbs, 45% fat) that is 149.1 g protein, 85.2 g carbs and 85.2 g fat a day — the carb and fat grams land equal by coincidence, because 20% of calories at 4 kcal per gram and 45% at 9 kcal per gram happen to divide to the same weight.
Frequently asked questions
What are my macros at 2,000 calories on a balanced split?
Balanced (30/40/30): 150 g protein, 200 g carbs, 66.7 g fat. High-protein (40/30/30) moves it to 200 g protein and 150 g carbs; keto (20/5/75) drops carbs to 25 g and pushes fat to 166.7 g. Same calories, very different plates.
How much protein do I actually need?
General guidance clusters around 1.6–2.2 g per kg of body weight for people training to build or keep muscle, and 0.8 g/kg as the sedentary floor. On the high-protein split at 2,000 kcal you get 200 g — enough for most lifters up to about 100 kg.
Should I use the calorie number or build my TDEE?
If you already track and know your maintenance calories, enter the number — real data beats any formula. If you are starting cold, the TDEE build is the honest estimate: a 30-year-old man, 80 kg, 178 cm, moderately active, lands at about 2,740 kcal.
Why do the grams not add back to exactly my calories?
Rounding. Each gram figure is rounded to a tenth, so the check sum can drift by a few kcal — under 0.5% either way. Real food labels round far more aggressively than this.
📏 What is the fat percentage today?
The Body Fat Calculator uses the Navy tape method to split your weight into fat mass and lean mass — the baseline macros then work from.
Does this calculator use net carbs for the keto split?
No. The keto preset takes 5% of your calories and divides by 4 kcal per gram, which is a total-carb figure. If you track net carbs, subtract fibre grams yourself from the foods you log — labels differ by country on whether fibre is already inside the carb line, so the tool leaves that adjustment to you rather than baking in one convention.
Should training days and rest days have different macros?
This tool gives one daily set of grams, which is what most people can actually stick to. Splitting the week into training and rest targets is possible — usually more carbs around training, the same protein every day — but the weekly average is what drives the result, and a single consistent target is easier to hit than two rotating ones.