A formula you can check
Portion calories = total recipe calories × portion weight ÷ cooked dish weight.
In this illustrative example, an 800 g dish contains 1,200 kcal. A 200 g portion is one quarter: 300 kcal. Each 100 g contains 150 kcal. The same proportion applies to protein, fat and carbohydrate.
Where to get the recipe total
For each ingredient, multiply its calories per 100 g by the weight used, then divide by 100. Add the results, including oils, sauces and extras. This tool divides a known total; it does not identify ingredients from their names.
Grams and ounces both measure weight
Use one unit for the whole dish and your portion. Switching units converts the entered weights. Fluid ounces (fl oz), cups and millilitres need a separate conversion to mass.
When to adjust the estimate
The result assumes an even distribution of ingredients. Discarded fat, leftover marinade or an uneven serving can change the composition. Meat and a separate side may be better logged individually. This calculator does not estimate your daily calorie needs.