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Salt Labels: Grams of Salt and Sodium Milligrams

By the Clinical Research Explained Editorial Team. Educational unit guide, not medical or dietary advice. Sources last checked October 6, 2026.

The Short Answer: Salt and Sodium Are Different Quantities

Salt (sodium chloride) and sodium (one element inside salt) are not the same quantity, so a number printed in grams of salt cannot be compared with a number printed in milligrams of sodium until one is converted. The World Health Organization states the relationship this way: “1 gram of salt is equivalent to 400 mg of sodium,” so 5 g of salt is equivalent to 2,000 mg of sodium (WHO, Sodium reduction fact sheet, updated 11 May 2026). Going the other way, divide milligrams of sodium by 400 to get grams of salt.

On a United States Nutrition Facts label, sodium is shown in milligrams (for example, “Sodium 850mg” in FDA's sample label comparison), not in grams of salt (FDA, How to Understand and Use the Nutrition Facts Label, page dated 03/05/2024). Labels and studies elsewhere may report “salt” in grams instead. In Regulation (EU) No 1169/2011, for example, “salt” is defined as a calculated salt equivalent: salt = sodium × 2.5 (Annex I, as retained in UK legislation). That is the same relationship as WHO's, written as a multiplier (1 ÷ 2.5 = 0.4, so 400 mg of sodium per gram of salt).

Why the Two Units Get Mixed Up

FDA's guidance notes that “table salt” and “sodium” are often used interchangeably but do not mean the same thing: table salt is sodium chloride, and sodium is a mineral and one of the chemical elements found in salt (FDA, Sodium in Your Diet). A news story that says “limit salt to 5 grams” and a label that says “sodium 480 mg” are therefore using different units for related, but not identical, amounts.

Two scale differences add to the confusion. Grams and milligrams differ by a factor of 1,000 (1 g = 1,000 mg), and salt weighs about two and a half times as much as the sodium it contains. Skipping the gram-to-milligram step can produce a 1,000-fold error, and skipping the salt-to-sodium step can produce a 2.5-fold error.

The Conversion Question Sheet

Use these questions in order when a label, news article, or study reports a salt or sodium number. Each answer tells you what to write down before comparing it with any other figure.

  1. What is being measured: salt or sodium? Look for the word next to the number. “Sodium” or “Na” means the element. “Salt,” “table salt,” “NaCl,” or “salt equivalent” means the compound.
  2. What is the unit: g, mg, or mmol? Write it down with the number. Labels in the United States list sodium in mg (FDA, above). A study may use another unit, such as millimoles (mmol); by our own arithmetic from sodium's atomic weight, 1 mmol of sodium is about 23 mg.
  3. What is the quantity “per”? A figure may be per serving, per 100 g, per package, or per day. A per-serving number cannot be compared with a per-day number without knowing how many servings were eaten.
  4. Which conversion factor applies?
    • Salt in grams to sodium in milligrams: multiply grams by 400 (WHO, above).
    • Sodium in milligrams to salt in grams: divide milligrams by 400, or equivalently multiply by 2.5 and divide by 1,000 (WHO, above; EU definition, above).
  5. Is the number an estimate or a measurement? A converted “salt” figure is a calculation from sodium, not a separate measurement of table salt. The EU text itself calls it a “salt equivalent content calculated using the formula” (EU Annex I, above).
  6. Was the number rounded? WHO reports a global mean adult intake of 4,278 mg/day of sodium and describes it as equivalent to 11 g/day of salt in 2021 (WHO, above). Converting exactly gives 10.7 g, so a rounded sentence in a headline can differ from the arithmetic.
  7. What reference is being used for comparison? A threshold in a study, a Daily Value on a label, and a recommendation in a guideline can each use different units and different target populations. Confirm the unit and the population before comparing.

Worked Examples

The WHO and FDA figures below come from the cited pages. The conversions are simple arithmetic using the WHO factor of 400 mg of sodium per gram of salt, and were checked by calculation on October 6, 2026. The 480 mg label is a made-up illustration, not a real product.

  • 5 g of salt: 5 × 400 = 2,000 mg of sodium. This matches WHO's stated pairing of “less than 2000 mg/day of sodium (equivalent to less than 5 g/day salt)” for adults (WHO).
  • 2,300 mg of sodium: 2,300 ÷ 400 = 5.75 g of salt. FDA lists the sodium Daily Value as less than 2,300 mg per day, and describes that amount as about 1 teaspoon of table salt (FDA, Sodium in Your Diet; FDA, Daily Value on the Nutrition and Supplement Facts Labels).
  • 3,400 mg of sodium: 3,400 ÷ 400 = 8.5 g of salt. FDA states that Americans eat about 3,400 mg of sodium per day on average (FDA).
  • Hypothetical label reading “Sodium 480 mg” per serving: 480 ÷ 400 = 1.2 g of salt equivalent per serving. As a share of a 2,300 mg Daily Value, 480 ÷ 2,300 is about 21%. FDA's guide says 5% DV or less per serving is considered low and 20% DV or more is considered high (FDA, Daily Value).
  • Hypothetical package reading “Salt 1.5 g per 100 g”: 1.5 × 400 = 600 mg of sodium per 100 g.

What This Sheet Can and Cannot Establish

The sheet can tell you whether two numbers are expressed in comparable units, and it can show you when a headline figure has been rounded. It cannot tell you whether a particular amount is appropriate for a particular person, because that depends on factors this page does not assess. It also cannot tell you whether a product is better or worse than another one.

  • The factor is a rounded convention. Sodium chloride is made of sodium and chlorine. Using standard atomic weights (sodium about 22.99, chlorine about 35.45), the exact ratio is about 2.54 rather than 2.5, so exact salt-to-sodium conversions are about 393 mg of sodium per gram of salt instead of 400 mg. This ratio is our own arithmetic and not a figure from WHO or FDA; the published rounded factor is the one labels and the WHO fact sheet use.
  • A salt figure computed from sodium assumes all the sodium came from salt. The formula starts from the sodium number and does not distinguish where the sodium came from. This is an inference from how the formula works, and the sources above do not discuss it directly.
  • Different documents use different reference values. WHO's recommendation for adults and FDA's Daily Value are stated separately by each organization, for the populations and purposes each defines. This page reports what each source says and does not rank them.
  • Teaspoon equivalents are approximations. FDA's “about 1 teaspoon” statement is worded as approximate, so the gram or milligram figure is the more precise number to work from.

Information That Is Often Missing

When a label or study uses a number without the pieces below, the conversion cannot be checked. A short list of what to look for:

  • Whether “salt” or “sodium” is meant, and the exact unit.
  • The serving size or base amount, and the number of servings per container.
  • Whether a quoted intake is a daily average, a single meal, or a laboratory measurement such as a urine value.
  • How the authors or manufacturer converted between units, and whether they rounded.

Who Should Ask a Professional

This page does not recommend any intake level, and the figures above are cited as what the organizations state, not as personal targets. If a clinician or registered dietitian has given you a sodium or salt limit, ask them which unit that limit is written in and how it applies to you, including how to read the labels on foods you eat. People who have been told to change their diet or medicines because of a health condition should follow their own clinician's instructions and should not use this sheet to change treatment on their own.

For questions about how a specific label must be written or whether a package's sodium information is accurate, the relevant authority is the food regulator in the country where the product is sold, such as FDA in the United States. Questions about whether a study's conclusions apply to a patient are a matter for the treating clinician.

What You Can Do Next

  1. Pick one label or news figure and run it through the seven questions above, writing down the unit and the “per” basis.
  2. Convert both numbers into the same unit before comparing them.
  3. If a number does not make sense after conversion, check the original source for rounding and for the serving size.
  4. Bring unresolved questions about your own limit to a clinician or registered dietitian.

If you are looking at a separate question, whether sea salt and processed salt differ, our related article Sea Salt vs. Processed Salt discusses that topic. This page does not evaluate its claims.

About This Page and Editorial Independence

Clinical Research Explained is an independent educational publication. It is not a clinic, a hospital, or a university department, it provides no medical care, and its name should not be read as implying clinical care or institutional affiliation. The site may earn compensation from links on other pages, but this article contains no affiliate links, product rankings, or product recommendations, and it was prepared from the public sources listed below without testing any product. See our About page, Editorial Standards, Editorial Team and Review Process, Corrections Policy, and Medical Disclaimer. To report an error in this article, use the contact route on the Corrections Policy page.

Sources Checked

  • World Health Organization. Sodium reduction (fact sheet, last updated 11 May 2026). Checked October 6, 2026. Supports: 1 g salt = 400 mg sodium; adult recommendation; 2021 global mean intake.
  • U.S. Food and Drug Administration. Sodium in Your Diet (page dated 03/05/2024). Checked October 6, 2026. Supports: table salt and sodium are not the same thing; the sodium Daily Value of less than 2,300 mg; the “about 1 teaspoon of table salt” statement; average intake of about 3,400 mg.
  • U.S. Food and Drug Administration. How to Understand and Use the Nutrition Facts Label (page dated 03/05/2024). Checked October 6, 2026. Supports: sodium shown in milligrams on the label.
  • U.S. Food and Drug Administration. Daily Value on the Nutrition and Supplement Facts Labels (page dated 03/05/2024). Checked October 6, 2026. Supports: 2,300 mg sodium Daily Value; %DV definition; 5% and 20% guide.
  • Regulation (EU) No 1169/2011, Annex I, definition of “salt,” UK-retained copy on legislation.gov.uk. Checked October 6, 2026. Supports: salt = sodium × 2.5 as the labeling definition. This is the UK-retained copy of the regulation, and we did not check the current EU consolidated text.

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