Where the numbers come from
Every figure on this site comes from a named source and can be traced to one record in it. No figure is typed in by hand, estimated, or produced by a computer model.
The sources
Food figures come from FoodData Central, the food composition database of the United States Department of Agriculture (USDA). Three parts of it are used, in this order:
- Foundation Foods: values measured in a laboratory for basic foods.
- SR Legacy: the final release of the USDA Standard Reference database, which covers a wide range of everyday foods.
- Survey Foods (FNDDS): foods as people eat them, including mixed dishes, with household portions.
USDA publishes this data in the public domain. It is not connected with this site and has not reviewed it.
The release used
USDA asks to be cited. This is the citation for the data on this site:
U.S. Department of Agriculture, Agricultural Research Service, Beltsville Human Nutrition Research Center. FoodData Central. [Internet]. [cited 11 October 2026]. Available from https://fdc.nal.usda.gov/. Releases used: Foundation Foods, April 2026; SR Legacy, April 2018; Survey Foods (FNDDS 2021-2023), October 2024.
The date of each USDA release used:
- USDA FoodData Central, Foundation Foods: 30 April 2026
- USDA FoodData Central, SR Legacy: 2018-04
- USDA FoodData Central, Survey Foods (FNDDS): 31 October 2024
Data bundle on this site: data-2026-10-11.
The method
- One record for each food. A food on this site is tied to exactly one USDA record. Foundation Foods is used first, then SR Legacy, then Survey Foods. The record number is shown on the food page, with a link to it.
- Portions come from the source. "1 slice" or "1 cup" is the measure in the USDA record, with the weight USDA gives for it.
- The only words written by hand are the plain names of foods. No number is.
- Sums are done on the full, unrounded values. Rounding happens once, when a figure is shown.
How figures are rounded
One rule is used everywhere: on a food page, in a total, in print and on a shared card.
| Figure | Shown as |
|---|---|
| Sodium, potassium, phosphorus | Whole milligrams (mg) |
| Protein, carbohydrate, sugars, fiber, saturated fat | One decimal place below 10 g. Whole grams from 10 g |
| Share of a limit you entered | Whole percent. Below 1, "less than 1%" |
| Calories | Whole calories |
A total is worked out from the unrounded values and then rounded. So a total may differ by 1 from the sum of the rounded figures shown beside it.
An amount that is above zero but too small to show is written "less than 1 mg" or "less than 0.1 g". For a food from USDA, a 0 always means the source records zero. A figure from a book recipe is shown exactly as the book prints it, and a figure you copy from a pack is shown as you typed it; a book or a pack may print 0 for a very small amount.
When the source has no figure
If a USDA record has no figure for a nutrient, the page says "not reported". It never shows a zero in its place, and the gap is never filled with an estimate.
A total that includes such a food reads "at least", with the number of items not reported.
Why phosphorus is often missing
United States rules require potassium on the Nutrition Facts label. They do not require phosphorus. So most packs do not print a phosphorus figure, and data that comes from labels usually does not have one.
USDA measures phosphorus for many foods, but not for all of them. Where the record has no figure, this site says "not reported".
Added phosphates are a separate matter. They are named in the ingredient list on a pack. The amount of phosphorus they add usually is not.
The label rule is quoted, with its source, on the page about potassium and phosphorus on the label.
"Typical value: brands differ"
A USDA record for a general food, such as a kind of bread or soup, describes a typical example. The pack in your hand may differ, sometimes by a lot. Food pages for such foods carry the line "Typical value: brands differ, so check the label".
The figures on the pack are the ones that apply to that pack.
If you find an error
Figures can contain errors: in the source, or in how this site was built from it. If a number looks wrong, tell us through the Contact page. Say which food, which portion, the figure you saw, and the figure on the source.
- We check the figure against the USDA record.
- If the site is wrong, we find the cause and correct it in the data build, not by hand.
- We check whether the same cause affected other foods.
- We list the change, with its date, on the Corrections page: what the figure was and what it is now.
Every change made so far is on the Corrections page.