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How NutriCalcPro calculates nutrition data: where our numbers come from, how we apply FDA and international rounding rules, and when you should use lab testing instead of a database.
NutriCalcPro sources nutrition data from government-maintained databases that underpin food regulations in their respective markets. We do not fabricate, interpolate, or extrapolate values — we use verified laboratory-tested data from authoritative sources.
https://fdc.nal.usda.gov
Our primary source. USDA FDC is the US federal nutrition database maintained by the Agricultural Research Service. It contains analytical data from laboratory testing of thousands of foods — it is the same database underpinning FDA-regulated food labels. Foundation Foods entries come from direct lab analysis. SR Legacy (Standard Reference) values are the historic USDA database used for decades in food policy.
UK-specific nutrient values from the UK Food Standards Agency. Used for UK FSA label generation and for cross-validating European ingredient data where USDA FDC coverage is limited for UK-specific foods (e.g., certain British cheeses, baked goods, prepared meals).
Food Standards Australia New Zealand (FSANZ) nutrient data tables. Used for Australian FSANZ label generation. Covers Australian and New Zealand foods with locally appropriate serving size conventions.
For branded or processed ingredients (e.g., a specific brand of canned tomatoes), users can manually enter nutrition values from the supplier's specification sheet or product label. These values take precedence over database values for that ingredient.
Every nutrition calculation follows the same steps:
Each ingredient name is matched to the database using a combination of semantic search (vector embeddings), exact name matching, and synonym resolution. The best-match entry is selected; you can override the match if needed.
The quantity in your recipe (e.g., "2 cups of flour") is converted to grams using ingredient-specific density values. For liquids, standard volume-to-weight conversions are applied. For yield items (e.g., "1 large egg"), standard USDA serving weights are used.
Nutrient values per 100g from the database are scaled to the recipe quantity for each ingredient. All ingredients are summed to give total recipe nutrition, then divided by serving count to give per-serving values.
The exact rounding rules for the selected label region are applied. FDA rules (21 CFR 101.9), EU FIC rules, UK FSA rules, SFDA GSO rules, Canadian CFIA rules, and FSANZ rules each specify different precision, threshold, and display requirements for each nutrient — all applied automatically.
Daily Value percentages are calculated using the FDA's 2020 reference daily intakes (for US labels) or the equivalent regional reference values. %DV is rounded to the nearest 1% and follows the FDA's ≤1% → "less than 1%" display convention.
NutriCalcPro applies these rounding rules automatically for US FDA labels. EU, UK, Canadian, SFDA, and Australian label formats each follow their own regional rules — applied when you select the corresponding label format.
| Nutrient | Rounding rule | Regulation |
|---|---|---|
| Calories | Rounded to nearest 5 kcal (below 50 kcal: nearest 5; 50 kcal+: nearest 10) | FDA 21 CFR 101.9(c)(1) |
| Total Fat, Saturated Fat, Trans Fat | Rounded to nearest 0.5g (below 5g); nearest 1g (5g+); "0g" if <0.5g | FDA 21 CFR 101.9(c)(2–4) |
| Cholesterol | "0mg" if <2mg; nearest 5mg (2–5mg); nearest 5mg (5mg+) | FDA 21 CFR 101.9(c)(7) |
| Sodium | "0mg" if <5mg; nearest 5mg (5–140mg); nearest 10mg (140mg+) | FDA 21 CFR 101.9(c)(8) |
| Total Carbohydrate | Rounded to nearest 1g; "less than 1g" if 0.5–0.9g; "0g" if <0.5g | FDA 21 CFR 101.9(c)(6) |
| Dietary Fiber | Same as Total Carbohydrate rounding | FDA 21 CFR 101.9(c)(6)(i) |
| Total Sugars / Added Sugars | Same as Total Carbohydrate rounding | FDA 21 CFR 101.9(c)(6)(ii–iii) |
| Protein | Rounded to nearest 1g; "less than 1g" if 0.5–0.9g; "0g" if <0.5g | FDA 21 CFR 101.9(c)(5) |
| Vitamin D, Calcium, Iron, Potassium | Expressed as %DV; rounded to nearest 2%DV (below 10%DV) or nearest 5%DV (10%DV+) | FDA 21 CFR 101.9(c)(8)(iv) |
The most common question from food manufacturers: when do I need a lab test?
Database calculation is appropriate for
Lab testing is recommended when
Every label NutriCalcPro generates uses verified USDA FDC data, applies the correct regional rounding rules, and outputs a compliance-ready Nutrition Facts panel.