Compare Sodium Fairly: A Per-100g Food Label Calculator
A food with 220 mg sodium in a 40 g serving can contain more sodium per 100 g than one with 300 mg in a 100 g serving. Compare labels on the same weight basis instead of trusting the front-of-pack claims.
The decision this workbook helps you make
The mathematical comparison is sodium per 100 g = labelled sodium mg ÷ labelled serving g × 100. This normalizes different serving sizes; it does not prescribe a daily sodium goal or account for every component of a meal. On U.S. Nutrition Facts panels the FDA lists 2,300 mg as the sodium Daily Value for adults and children ages 4 and over. Personalized medical advice may differ.
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Values are fictional examples, not real observations or product claims. This tool runs locally in the page and does not save or transmit entries.
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How to interpret your result
Check that both labels use sodium rather than salt, that units match, and that the amounts reflect the product as actually eaten. For a planned portion, calculate sodium per portion separately. Products may differ substantially in calories, protein, ingredients and allergens, so sodium is only one decision factor.
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Primary reference and limitations: FDA: sodium and the Nutrition Facts label. This original worksheet is educational, not professional diagnosis, clinical advice, or a claim of verified user results.