Salt to Sodium Converter for Food Labels
Use this salt to sodium converter to turn grams of salt into milligrams of sodium, or sodium back into salt, and add up the salt in a day’s food.
Convert salt and sodium
Amount to convert (example shown; replace it with your own)
Day’s tally, optional (example foods and label amounts shown; replace them with your own)
How the salt to sodium converter works
Salt on a food label is sodium multiplied by 2.5, so the salt to sodium converter multiplies or divides by that factor and then moves between grams and milligrams (1 g = 1,000 mg):
salt (mg) = sodium (mg) × 2.5
sodium (mg) = salt (g) × 1,000 ÷ 2.5
With the chemical ratio switched on, the factor comes from the atomic weights of sodium (22.990) and chlorine (35.45) instead:
salt = sodium × (22.990 + 35.45) ÷ 22.990 ≈ sodium × 2.542
Whatever you type, the converter shows the same amount as salt in grams and milligrams and as sodium in milligrams and grams. Results are rounded to about four significant figures, and the page says so when rounding changes a value.
Worked example: 600 mg of sodium
A US label lists 600 mg of sodium per serving. This is how much salt that is under each rule:
| Shown as | Food-label rule | Chemical ratio |
|---|---|---|
| Salt (g) | 1.5 g | 1.525 g |
| Salt (mg) | 1,500 mg | 1,525.2 mg |
| Sodium (mg) | 600 mg | 600 mg |
| Sodium (g) | 0.6 g | 0.6 g |
Worked example: adding up a day
The tally converts each food to both salt and sodium, so labels from different countries can be added together. With the food-label rule and these example amounts:
| Food | Label says | Salt | Sodium |
|---|---|---|---|
| Bread (2 slices) | 0.9 g salt | 0.9 g | 360 mg |
| Instant noodles (1 pack) | 1,400 mg sodium | 3.5 g | 1,400 mg |
| Crisps (small bag) | 0.4 g salt | 0.4 g | 160 mg |
| Total | 4.8 g | 1,920 mg |
That total is 83.5% of the US FDA Daily Value for sodium. These foods and amounts are only an example; use the figures on your own labels.
Why do labels multiply by 2.5?
Labels multiply by 2.5 because EU food labelling law defines it that way. Regulation 1169/2011 says “salt” on a label means the salt equivalent, calculated as sodium × 2.5. It is worked out from the total sodium in the food, so the figure is a salt equivalent rather than a measure of added table salt alone. WHO uses the same rounded relationship: 1 g of salt is equivalent to 400 mg of sodium.
The exact chemistry is slightly different. Sodium chloride is about 39.3% sodium by mass, so pure salt contains 1 g of sodium for every 2.542 g of salt. The chemical ratio therefore gives about 1.7% more salt for the same sodium. Because labels and health guidelines use the 2.5 rule, keep the salt to sodium converter on the food-label rule when comparing with them, and use the chemical ratio when you are working with pure salt, such as a weighed amount for a recipe.
How much salt is too much?
For adults in the general population, WHO recommends less than 5 g of salt a day, which is less than 2,000 mg of sodium. The US FDA Daily Value for sodium is less than 2,300 mg a day, and it is the amount behind the % Daily Value on Nutrition Facts labels. As a general guide, the FDA treats 5% DV or less of sodium per serving as low and 20% DV or more as high. The daily tally in the salt to sodium converter shows your total in both units, so you can compare it with either reference.
These are population reference amounts, not personal targets. Children need less: WHO adjusts the adult amount down for children aged 2 to 15 by their energy needs, and the FDA says limits are lower for children under 14. People with high blood pressure, kidney disease or other conditions may be given different advice, so ask a doctor or registered dietitian about your own limit. For eating ideas, see our high blood pressure diet guide and the DASH diet, which is built around lower sodium.
Why not convert salt to teaspoons?
A teaspoon measures volume, while salt and sodium are amounts by weight, and the weight of a spoonful of salt is not fixed. It depends on the size and shape of the grains and how tightly they settle, so fine table salt, coarse salt and flaky salt all give different answers. That is why official advice describes spoon measures only roughly: WHO calls 5 g of salt just under a teaspoon, and the FDA calls 2,300 mg of sodium about 1 teaspoon of table salt. For other ingredients, our kitchen unit converter handles cups and spoons with exact definitions.
Reading salt and sodium on labels
- Check the basis. Labels may give salt or sodium per 100 g, per serving or per pack. Use the figure for the amount you actually eat; our nutrition label portion calculator scales label values to your portion.
- Packaged food counts most. The FDA reports that over 70% of dietary sodium in the US comes from packaged and prepared foods, not from salt added at the table.
- Labels are rounded. A label’s salt figure already carries the manufacturer’s rounding, so treat converted values as label-level precision.
- Balance with potassium. Fruit, vegetables and pulses are rich in potassium; see our list of foods high in potassium.
Whichever label you are holding, the salt to sodium converter turns it into the figure you need in seconds.
Sources for these figures
- EU Regulation 1169/2011, Annex I, point 11: salt = sodium × 2.5.
- IUPAC CIAAW abridged standard atomic weights: sodium 22.990, chlorine 35.45.
- WHO fact sheet: salt reduction: less than 5 g salt (2,000 mg sodium) a day for adults; 1 g salt = 400 mg sodium.
- US FDA: sodium in your diet: Daily Value of less than 2,300 mg sodium, % DV guide and sources of sodium.
Frequently Asked Questions
Multiply the sodium by 2.5. Food labels use this rule, so 400 mg of sodium is 1 g of salt and 600 mg of sodium is 1.5 g of salt. To go the other way, divide the salt by 2.5: 2 g of salt is 0.8 g, or 800 mg, of sodium. The converter does the arithmetic in either direction.
No. Table salt is sodium chloride, and sodium is only one of its two elements. By weight, sodium chloride is about 39.3% sodium and 60.7% chloride. Labels in the UK and EU show salt, while US Nutrition Facts labels show sodium in milligrams, so the same food can look very different depending on which figure is printed.
Using the food-label rule, 2,300 mg of sodium is 5.75 g of salt; the exact chemical ratio gives 5.847 g. 2,300 mg is the US FDA Daily Value for sodium, the amount behind the % Daily Value on Nutrition Facts labels. WHO recommends that adults have less than 2,000 mg of sodium, or less than 5 g of salt, a day.
Food labels use a round factor of 2.5, set in EU labelling law. Chemistry gives a factor of about 2.542, because sodium chloride is 39.3% sodium by mass. The chemical ratio gives about 1.7% more salt for the same sodium. Use the label rule to compare with labels and guidelines, and the chemical ratio for pure salt.
There is no exact answer, so this converter does not use teaspoons. The weight of a spoonful depends on the size of the grains and how tightly they settle, so fine table salt and coarse or flaky salt differ. WHO describes its 5 g limit as just under a teaspoon, and the US FDA calls 2,300 mg of sodium about 1 teaspoon of table salt. Weigh salt when the amount matters.