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Grams to Calories Calculator

Convert grams of each macronutrient into calories.

Your numbers

Results

Total calories
455 kcal
Protein (4/g)
120 kcal
Carbs (4/g)
200 kcal
Fat (9/g)
135 kcal
Alcohol (7/g)
0 kcal
Energy per gram

Protein 4 · Carbs 4 · Fat 9 · Fiber 2 · Alcohol 7 (kcal/g)

Protein and carbs supply 4 calories per gram, fat supplies 9, alcohol 7, and fiber about 2. Multiply grams by these values for calories.

Enter grams of each component for a calorie total and a per-macro breakdown.

How to convert grams to calories

To convert grams to calories, multiply each macronutrient's grams by its energy value and add them. Reverse it by dividing calories by the same numbers.

Worked example: 30 g protein × 4 = 120 calories.

Frequently asked questions

Protein supplies 4 calories per gram, the same as carbohydrates.

Fat supplies 9 calories per gram, more than double protein or carbs.

Divide the calories by the energy per gram: 4 for protein and carbs, 9 for fat, 7 for alcohol.

Results are estimates based on population averages and are not medical advice. Consult a doctor or registered dietitian nutritionist (RDN) before making large changes to your diet, especially for deficits over 2 lb (0.9 kg) per week, during pregnancy or nursing, or for anyone under 18.