Food Portion & Comparison Calculator
Look up rounded reference nutrition for common foods, convert a typical portion into grams and macros, and compare two foods on an equal basis.
Published by Reeve Editorial Team · Methods and sources updated
Nutrition for your portion
165 kcal
Chicken breast, roasted · 100.0 g
31 g protein · 0 g carbs · 3.6 g fat
Rounded reference snapshot · verify against a matching food entry or label.
Compare foods on the same basis
First food
100 kcal
Chicken breast, roasted · 60.6 g
18.8 g protein · 0 g carbs · 2.2 g fat
Rounded reference snapshot · verify against a matching food entry or label.
Second food
100 kcal
Lentils, cooked · 86.2 g
7.8 g protein · 17.3 g carbs · 0.3 g fat
Rounded reference snapshot · verify against a matching food entry or label.
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These are rounded reference values for unbranded foods. Match preparation method and raw or cooked state. Use the actual package label when available.
How this tool works
Each food uses rounded per-100-gram reference values and a representative common portion. The calculator multiplies the per-100-gram values by the selected gram amount.
The collection contains 29 rounded nutrition snapshots and eight raw-vegetable records derived from the FDA's published serving table. FDA records link to their source in the result. The collection is a small reference list, not a live food database.
The comparison view can hold weight constant, hold energy constant at 100 calories, or use each food's common portion. The chosen basis changes the question, so it can legitimately change which food appears higher in a nutrient.
Food composition varies with variety, maturity, cooking, drainage, formulation, and brand. Packaged-food labels and records that match the exact preparation should take priority over a generic reference.
Sources
Frequently asked questions
Are common portions exact?
No. A medium fruit, slice, fillet, scoop, or cup can vary. The gram amount shown is a representative reference, not a measurement of the food in front of you.
Why compare foods per 100 calories?
Holding energy constant can make differences in protein, carbohydrate, fat, and food mass easier to see. It does not make one food universally better.
Should I use raw or cooked values?
Match the food you actually measured. Cooking changes water content and therefore nutrition per gram, even when it does not meaningfully change the recipe's total energy.