About PortionCalc

PortionCalc answers a simple question quickly: how many calories and how much protein, fat and carbohydrate are in the amount of food in front of you. Every page is built around a calculator, so you can change the amount, the unit and the cooking method and see the result immediately.

Where the numbers come from

All nutrition values come from USDA FoodData Central, published by the U.S. Department of Agriculture. We use three of its datasets: the Food and Nutrient Database for Dietary Studies (FNDDS), SR Legacy and Foundation Foods. FoodData Central is in the public domain. Each food page names its source dataset and FDC ID.

How portions work

USDA measures the weight of common household portions, such as a cup of cooked rice or a large egg. We use those gram weights to convert cups, spoons, slices and pieces into grams, then scale the nutrients. Raw to cooked conversions use the calorie density of the raw and cooked versions of the same food, which reflects the water lost or gained in cooking.

What we do not do

We do not give medical or dietary advice, sell supplements or require an account. If you have a health condition or specific dietary needs, talk to a doctor or a registered dietitian.

Get in touch

Found a value that looks wrong or a food we should add? Email contact@portioncalc.com.