Salt Conversion Calculator (Table, Kosher, Sea)
Salt Conversion Calculator (Table, Kosher, Sea)
Convert between table salt, Morton coarse kosher, Diamond Crystal kosher and fine sea salt by volume and by weight, in both directions, from the makers’ own published densities — and see why weighing salt makes the problem vanish. Nitrite curing salts are not interchangeable with table salt at any ratio.
Salt by type
1 level teaspoon of table salt, replaced with Diamond Crystal kosher salt
Mass is the invariant; volume is not
- m
- mass of salt in grams — the quantity that is the same whichever salt you use
- g
- grams per level teaspoon for that particular salt, derived from its own Nutrition Facts panel
- 0.393393
- the sodium fraction of sodium chloride, 22.989 769 28 / (22.989 769 28 + 35.45)
- 1 tsp
- 4.928 92 mL, a sixth of a US fluid ounce. The volume is fixed; what fills it is not
Worked example
1 level teaspoon of table salt, replaced with Diamond Crystal kosher salt
Morton's table salt panel declares 590 mg sodium per quarter teaspoon, so a teaspoon is 4 × 0.590 / 0.3934 = 5.999 g
Diamond Crystal's panel declares 280 mg per quarter teaspoon, so a teaspoon of it is 2.847 g
So one level teaspoon of table salt is 6.00 g of salt — and USDA, measuring separately, publishes 6 g
6.00 g / 2.85 g per teaspoon = 2.11 level teaspoons of Diamond Crystal
Cook's Illustrated publish this swap as 2 teaspoons, which is the same answer to the precision a spoon can deliver — and both of them are 6.00 g on a scale
Grams per level teaspoon, and how each figure was obtained
| Salt | g per tsp | g per tbsp | g per US cup | mg sodium per ¼ tsp on the label | Cross-check |
|---|---|---|---|---|---|
| Table salt / fine salt | 6.00 | 18.00 | 288 | 590 | USDA (173468) publishes 6 g per teaspoon for table salt; this panel gives 6.00. |
| Morton coarse kosher salt | 4.88 | 14.64 | 234 | 480 | Morton’s own chart makes 1 tsp table salt equal 1 1/4 tsp of this, implying 4.80. |
| Diamond Crystal kosher salt | 2.85 | 8.54 | 137 | 280 | Cook’s Illustrated makes 1 tsp table salt equal 2 tsp of this, implying 3.00. |
| Morton fine natural sea salt | 5.19 | 15.56 | 249 | 510 | Morton’s chart substitutes this 1:1 with table salt, which would imply 6.00. |
Substituting by volume: what each maker and each test kitchen publishes
| Source | 1 teaspoon table salt equals | Implied g per tsp | The label figure |
|---|---|---|---|
| Morton Salt’s own conversion chart | 1¼ tsp Morton coarse kosher | 4.80 | 4.88 on the label — agrees to within 2% |
| Morton Salt’s own conversion chart | 1 tsp fine sea salt (a 1:1 swap) | 6.00 | 5.19 on the label — disagrees by 14% |
| Cook’s Illustrated | 1½ tsp Morton kosher | 4.00 | 4.88 on the label — Cook’s Illustrated implies 18% less |
| Cook’s Illustrated | 2 tsp Diamond Crystal kosher | 3.00 | 2.85 on the label — agrees to within 5% |
Nitrite curing salts — read this before you convert anything
| Product | What is actually in it | Substitutes for table salt at |
|---|---|---|
| Prague powder #1 / Insta Cure #1 / pink curing salt #1 | 6.25% sodium nitrite, 93.75% sodium chloride | No ratio. Never. |
| Prague powder #2 / pink curing salt #2 | 6.25% sodium nitrite, 4% sodium nitrate, 89.75% sodium chloride | No ratio. Never. |
| Table salt, kosher salt, sea salt, flake salt | Sodium chloride | The ratios in the table above |
Why a teaspoon of salt is not a teaspoon of salt
Measure salt by weight and the problem disappears. That is the whole answer, and everything below is why it is worth the trouble of a scale. By mass, every culinary salt is very nearly the same thing: sodium chloride, within a percent or two of every other, interchangeable one for one. By volume they differ by up to a factor of two. A level teaspoon of table salt is about 6.0 g. The same teaspoon of Diamond Crystal kosher salt is about 2.8 g. If a recipe was written with one and you cook it with the other, you are out by a factor of 2.11 on the single ingredient that cannot be taken back out.
Why a spoon cannot measure salt. A teaspoon measures about 4.93 millilitres of space, and what fills that space is salt and air in a proportion decided by the shape of the crystal. Table salt is fine, dense, nearly cubic and packs tightly, with an anti-caking agent to keep it flowing. Kosher salt is deliberately coarse, so that it can be picked up and seen. Diamond Crystal’s crystals are made by a different process again and come out as hollow flakes, which is why they weigh so little for their bulk. None of this changes the salt; all of it changes the spoon.
Where these numbers come from. Each figure in the table is derived from the manufacturer’s own Nutrition Facts panel. A panel declares the sodium in a quarter teaspoon; sodium chloride is 39.34% sodium by mass, so the salt in that quarter teaspoon is the declared sodium divided by that fraction. Doing this for Morton’s table salt gives 5.999 g per teaspoon, and USDA FoodData Central independently publishes 6 g per teaspoon for table salt — two separate measurements agreeing to better than a tenth of a per cent, which is what licenses the same method on the other three. Labels round sodium to the nearest 10 mg, so read every figure as good to about 2%.
The published substitution charts do not agree with each other. Morton’s own chart makes one teaspoon of table salt equal one and a quarter teaspoons of its coarse kosher salt, which implies 4.80 g per teaspoon and matches the label. Cook’s Illustrated make the same swap one and a half teaspoons, which implies 4.00 g — a fifth less salt. Both are honestly published and both are in the table. A 20% disagreement between two careful sources about a single spoonful is the strongest argument this page can make for weighing.
Nitrite curing salts are not on this ladder at all. Prague powder #1, Prague powder #2, Insta Cure and the products sold as “pink curing salt” are not salt with something added for colour. Prague powder #1 is 6.25% sodium nitrite and 93.75% sodium chloride; #2 adds 4% sodium nitrate. Sodium nitrite is a preservative dosed in parts per million of the meat and it is toxic at doses a kitchen reaches easily. One level teaspoon of #1 carries about 375 mg of sodium nitrite, which is the entire ingoing allowance permitted for roughly 1.9 kg of dry-cured meat under 9 CFR 424.22, and the limit for pumped and immersion-cured bacon is lower still at 120 ppm. There is no ratio at which a curing salt substitutes for table salt and no ratio at which table salt substitutes for a curing salt. The products are dyed pink precisely so that the mistake cannot be made in a jar. If you are curing, follow a published recipe and weigh the cure on a scale that reads to a tenth of a gram.
For the rest of a recipe’s measures, the cups to grams converter carries table salt along with 25 other ingredients, and the butter converter is the page that sends readers here when they swap salted butter for unsalted.
Frequently asked questions
Is a teaspoon of kosher salt the same as a teaspoon of table salt?
No, and the difference is large. A level teaspoon of table salt is about 6.0 g. The same teaspoon of Morton coarse kosher salt is about 4.9 g, and of Diamond Crystal kosher salt about 2.8 g — less than half. Swapping one for the other by volume changes how salty the dish is by a factor of two.
Why do salts differ so much by volume when they are all sodium chloride?
Because a spoon measures space, and the shape of the crystal decides how much of that space is air. Table salt is fine dense cubes that pack tightly. Kosher salt is coarse and irregular; Diamond Crystal’s is a hollow pyramid made by a different process again. Flake salt is thin plates that barely touch. By mass they are all very nearly the same substance and interchange one for one.
What is the simplest way to avoid the problem?
Weigh the salt. By mass, every culinary salt in the table above is within a percent or two of every other, so a recipe written in grams works with whatever is in the cupboard. Salt is also the ingredient where being wrong is most obvious and least fixable, which makes it the best possible argument for a set of kitchen scales.
Can I use pink curing salt or Prague powder instead of table salt?
No. Not at any ratio, not in any quantity, not in an emergency. Prague powder #1 is 6.25% sodium nitrite and Prague powder #2 adds sodium nitrate; these are preservatives dosed at a few hundred parts per million of the meat, not seasonings. One teaspoon carries around 375 mg of sodium nitrite — the entire regulated allowance for roughly 1.9 kg of dry-cured meat. It is dyed pink so that it cannot be confused with salt. This is a food-safety matter, not a matter of taste.
Why does this page not list flake salt such as Maldon?
Because no figure for it could be sourced that survives a sanity check. The only published number available is the maker’s own US Nutrition Facts panel, which declares 580 mg of sodium per quarter teaspoon — implying 5.9 g per teaspoon, which is denser than table salt and physically impossible for a flake. Rather than invent a plausible number, the page leaves flake salt out and says why. Weigh it, or crush it and treat it as fine salt.
Is low-sodium or ‘lite’ salt on this list?
No. Products sold as reduced-sodium salt are usually a blend of sodium chloride and potassium chloride, so they are a different substance with a different density and a different saltiness, and they are not a volume conversion away from table salt. Follow the packet.
Related calculators
References
- Morton Salt. Salt Conversion Chart (mortonsalt.com): 1 tsp table salt = 1¼ tsp coarse kosher salt = 1 tsp fine sea salt, and 1 cup table salt = 1¼ cups coarse kosher salt.
- America’s Test Kitchen / Cook’s Illustrated. Salt types and measurements: 1 teaspoon table salt = 1½ teaspoons Morton kosher salt = 2 teaspoons Diamond Crystal kosher salt.
- U.S. Department of Agriculture, FoodData Central: Salt, table (FDC 173468), whose published portions are 6 g per teaspoon, 18 g per tablespoon and 292 g per cup. Used as the independent check on the label-derived densities. A US Government work, public domain.
- USDA FoodData Central, Branded Foods: the Nutrition Facts panels for Morton table salt (FDC 402683), Morton coarse kosher salt (1108879), Morton fine natural sea salt (1041375) and Diamond Crystal kosher salt (2571981, 2526598). The declared sodium per quarter teaspoon on each panel is what the densities here are derived from.
- Gisslen W. Professional Cooking, College Version. Wiley, 2006, p. 827, for the compositions of Prague powder #1 (6.25% sodium nitrite, 93.75% sodium chloride) and Prague powder #2 (6.25% sodium nitrite, 4% sodium nitrate, 89.75% sodium chloride).
- Code of Federal Regulations, 9 CFR 424.22, Certain other permitted uses: sodium nitrite in pumped and immersion-cured bacon shall not exceed 120 ppm ingoing, and in dry-cured bacon 200 ppm ingoing. Cited to show the scale at which nitrite is dosed, which is what makes a volume substitution for table salt impossible.