Macro Calculator
Enter your daily calories and a split to get grams of carbs, protein and fat.
What this tool does
Carbohydrate and protein provide about 4 calories per gram and fat about 9. At 2,000 calories and a 40/30/30 split, that is 800 kcal of carbs (200 g), 600 kcal of protein (150 g) and 600 kcal of fat (67 g). Enter your calories and choose a split.
Splits your calories by percentage and converts each share to grams.
Shows both the calories and the grams for each macronutrient.
How to use it
- Enter your daily calories.
- Choose a preset split or custom percentages.
- Make sure custom percentages total 100.
- Read the grams of each macronutrient.
Why use this calculator
Converts a daily calorie figure and a macro split into grams of carbohydrate, protein and fat, using 4, 4 and 9 kcal per gram. Calorie targets tell you how much to eat but not what it is made of. Turning a split into grams makes it practical to compare with food labels.
Why we built it
We built the macro calculator to convert calories and a split into grams of carbs, protein and fat using 4, 4 and 9 kcal per gram. Set the calorie target with the calorie calculator and check resting needs with the BMR calculator.
Who this tool is for
- People planning meals around a calorie target
- Gym-goers tracking protein
- Students learning macronutrients
When to use it
- Planning meals around a calorie target.
- Checking a diet plan's numbers.
- Comparing food labels.
- Learning how calories map to macros.
How it works
Grams = calories × share ÷ calories per gram, with carbohydrate 4, protein 4 and fat 9 kcal per gram. Presets are example splits: balanced 40/30/30, lower carb 25/35/40 and higher protein 35/40/25 (carbohydrate/protein/fat).
Example: 2,000 kcal, 40/30/30: carbohydrate 800 ÷ 4 = 200 g, protein 600 ÷ 4 = 150 g and fat 600 ÷ 9 = 67 g.
This is an educational estimate from a published formula. It is not medical advice, a diagnosis or a substitute for a clinician who knows your history. If something about your health worries you, speak to a doctor or another qualified professional.
A worked example
These are the values the calculator opens with, so you can see exactly what it does with them. Change any value on the page and the result updates; the figures below come from the same calculation.
| Input | Value |
|---|---|
| Daily calories | 2000 |
| Macronutrient split | Balanced - 40% carbs, 30% protein, 30% fat |
| Custom carbs | 50 |
| Custom protein | 20 |
| Custom fat | 30 |
With those inputs, the calculator returns:
- Carbohydrate: 200 g
- Protein: 150 g
- Fat: 67 g
- Carbohydrate calories: 800 kcal
- Protein calories: 600 kcal
- Fat calories: 600 kcal
What you give it, and what you get back
| Item | Details |
|---|---|
| Calories | Daily target, 500 to 8,000. |
| Split | A preset or custom percentages totalling 100. |
| Output | Grams and calories for carbohydrate, protein and fat. |
Issues you may run into
| What you see | Why it happens | What to do |
|---|---|---|
| "Must total 100%" message | Custom percentages do not add to 100. | Adjust them. |
| Labels differ | Food labels round and fibre is counted differently. | Treat the grams as targets. |
| I need protein per kg | This is a percentage-based tool. | Convert using your body weight. |
Assumptions and limitations
- Percentage-based splits only.
- Does not set a calorie target; use the calorie calculator.
Frequently asked questions
What are macros?
Macronutrients: carbohydrate, protein and fat, the three sources of calories in food.
How many calories per gram are in each macro?
Carbohydrate 4, protein 4 and fat 9.
What macro split is best?
It depends on your goals, health and preferences. A dietitian can advise.
Does it count alcohol?
No. Alcohol has about 7 kcal per gram.
How do I find my calories?
Use the calorie calculator for an estimate of daily needs.
Is my information sent anywhere?
No. The calculation runs in your browser and nothing leaves the page.
Sources and accuracy
Gram targets come from the acceptable macronutrient distribution ranges in the Dietary Guidelines for Americans, converting percentage shares of daily calories into carbohydrate, protein and fat grams using the standard energy values of 4, 4 and 9 calories per gram.
Figures last checked against the source on . Standards and rates can change — if you are relying on this for something that matters, confirm against the source above. Think a figure is wrong or out of date? Send a correction.