Nutrition labels use these factors, so you can check a label or estimate calories for a homemade dish.
How to use the Calories from Macros Calculator
- Protein
- Carbohydrate
- Fat
- Alcohol
Results update as you type, and every field accepts the units shown in its menu.
How it works
Multiply each macronutrient by its energy factor and add them.
Inputs explained
| Field | What to enter |
|---|---|
| Protein | In g |
| Carbohydrate | In g |
| Fat | In g |
| Alcohol | In g |
What each result means
- Calories = 4×[Protein] + 4×[Carbohydrate] + 9×[Fat] + 7×[Alcohol]
- Kilojoules = [Calories]×4.184
- From protein = 4×[Protein]÷[Calories]×100
- From carbs = 4×[Carbohydrate]÷[Calories]×100
- From fat = 9×[Fat]÷[Calories]×100
Example values
How the main result changes when Protein changes and everything else stays at the example values above:
| Protein (g) | Calories (kcal) |
|---|---|
| 12.5 | 345 |
| 18.75 | 370 |
| 25 | 395 |
| 31.25 | 420 |
| 37.5 | 445 |
| 50 | 495 |
Formula
kcal = 4 × protein + 4 × carbs + 9 × fat + 7 × alcoholWorked example
Inputs — Protein: 25 g; Carbohydrate: 40 g; Fat: 15 g; Alcohol: 0 g.
Results — Calories = 395 kcal; Kilojoules = 1,653 kJ; From protein = 25.3 %; From carbs = 40.5 %; From fat = 34.2 %.
Frequently asked questions
Does fibre count as carbohydrate?
On U.S. labels it is included in total carbs; it provides about 2 kcal/g.
Why might a label differ slightly?
Labels round values and may use specific factors for some foods.
What formula does the Calories from Macros Calculator use?
kcal = 4 × protein + 4 × carbs + 9 × fat + 7 × alcohol.