Kosher Salt vs. Table Salt: How They Compare

Kosher salt and table salt are the same substance, sodium chloride, and about the same share of each is sodium.¹² What separates them is the grain and what goes in the box. Table salt is made of tiny, uniform crystals and usually carries an anticaking agent, and often iodine.¹ Kosher salt is coarse-grained, rarely iodized, and named for its use in koshering meat.³ The grain matters more than it sounds, because it decides how much salt fits in a spoon: about 6 grams of table salt per teaspoon, 4.8 grams of Morton kosher salt and 2.8 grams of Diamond Crystal.⁴

Side by side

	Kosher salt	Table salt
What it is	Coarse-grained sodium chloride, named for koshering meat¹³	Fine-grained sodium chloride¹²
How it’s made	Diamond Crystal: brine heated and stirred in open pans, forming hollow pyramid crystals. Morton: vacuum evaporators, then pressed flat between rollers⁴	Tiny, uniform crystals from rapid vacuum evaporation (ATK);¹ the AHA describes it as mined and processed to a fine texture²
Additives	Morton: yellow prussiate of soda, an anticaking agent.⁵ Diamond Crystal: none, per ATK⁴	Usually an anticaking agent.¹ Morton iodized: calcium silicate, dextrose, potassium iodide⁶
Iodine	Not usually iodized⁷³	Iodized or plain. US iodized salt: 45 mcg iodine per gram⁷
Grams per teaspoon (ATK)	Morton 4.8 g; Diamond Crystal 2.8 g⁴	About 6 g, regardless of brand⁴
Grams per ¼ teaspoon (Morton labels)	Morton kosher 1.2 g⁵	Morton iodized 1.5 g⁶
Sodium per ¼ teaspoon (Morton labels)	480 mg⁵	590 mg⁶
Dissolving	More slowly than table salt³	Faster than kosher salt³
Main job	Seasoning by hand; ATK’s first choice for seasoning meat¹	Measured cooking and baking, and the shaker⁶
Flavor (editorial)	Salty; Diamond Crystal crisp and light, Morton harder	Salty; fine and quick to dissolve on the tongue
Price	No dated, sourced comparison found	No dated, sourced comparison found

The label rows compare one brand’s products with each other. They are rounded serving sizes, not laboratory weighings.

Grain: the difference that matters

How the salt is crystallized sets the grain. ATK describes table salt’s tiny, uniform crystals as the product of rapid vacuum evaporation.¹ Kosher salt’s two big brands get their large grains in different ways: Diamond Crystal grows hollow pyramids in open, heated pans of brine, while Morton presses vacuum-evaporated salt through rollers into thin flakes.⁴

Three things follow from the grain.

How much fits in a spoon. A coarse grain leaves air between crystals, so a spoonful holds less salt. The AHA notes that a coarse salt has less sodium per teaspoon only because fewer crystals fit.² Weight for weight, they are the same.
How fast it dissolves. Tufts notes that kosher salt’s coarser grains dissolve more slowly than table salt, which can help season the surface of food.³
How it handles. ATK’s testers make kosher salt their first choice for seasoning meat because the coarse grains are easy to pinch and spread.¹ On buttered bread, they preferred Diamond Crystal’s “delicate and fleeting crunch.”⁴

Where the name comes from

Kosher salt is named for its use, not for how it is made. Its coarse grains were used to draw blood out of meat, as Jewish dietary law requires.³¹ Morton states that its kosher salt is kosher certified.⁵ A common explanation adds that the large grains sit on the meat’s surface without dissolving and so keep it from tasting too salty; we found no source for that mechanism.

What’s in the box

Table salt usually contains an anticaking agent that helps it pour.¹ Morton’s iodized table salt lists salt, calcium silicate (an anticaking agent), dextrose and potassium iodide.⁶ Under US rules, salt with added iodide may be labeled “iodized salt” and must state that it supplies iodide, a necessary nutrient, and salt with an anticaking agent may be labeled “free flowing.”⁸

Kosher salt is not iodized and usually has nothing else added.³ The exception is Morton’s, which contains yellow prussiate of soda as an anticaking agent; ATK reports that Diamond Crystal contains none.⁵⁴ So “kosher salt has no anticaking agent” is true of one major brand, not both.

Do the additives change the taste? ATK’s tasters found no detectable taste difference between iodized and noniodized salt.¹ In a separate test, broths seasoned with equal weights of Morton and Diamond Crystal tasted the same.⁴

Measuring: where the swap goes wrong

Measured by weight, the two are interchangeable. Measured by volume, they are not, and the published conversions disagree.

Salt	Grams per teaspoon	Source
Table salt	About 6 g, regardless of brand	ATK⁴
Morton kosher	4.8 g	ATK⁴
Diamond Crystal kosher	2.8 g (rounded to 3 g in a later ATK article)	ATK⁴⁹

For 1 teaspoon of table salt: the sources disagree

Source	Morton kosher	Diamond Crystal
ATK’s rule of thumb	1½ teaspoons	2 teaspoons
Morton’s conversion chart (Morton products only)	1¼ teaspoons	not covered
Computed from ATK’s own gram weights (6.0 ÷ 4.8 and 6.0 ÷ 2.8)	1¼ teaspoons	about 2⅛ teaspoons
Computed from Morton’s own label weights (1.5 g ÷ 1.2 g per ¼ teaspoon)	1¼ teaspoons	not covered

Sources: ATK rule,¹ Morton chart,¹⁰ ATK weights,⁴ Morton labels.⁶⁵ Three of the four routes give 1¼ teaspoons of Morton kosher; ATK’s own rule of thumb gives more. We publish the disagreement rather than pick one (treatment: Disputed). The same table appears on our kosher salt page. ATK itself recommends weighing salt.⁹

Can one stand in for the other?

Yes. Any salt substitutes for another by weight; by volume, adjust for the grain. These treatments follow our kosher salt substitute page.

Swap	Starting amount	Treatment
Either, measured by weight	The same weight	Computed
Morton kosher in place of 1 teaspoon table salt	1¼ teaspoons (ATK’s rule says 1½)	Disputed (see above)
Diamond Crystal in place of 1 teaspoon table salt	2 teaspoons (ATK’s weights imply about 2⅛)	Disputed (see above)
Table salt in place of 1 teaspoon Morton kosher	¾ teaspoon, then taste	Method
Table salt in place of 1 teaspoon Diamond Crystal	½ teaspoon, then taste	Method
Table salt in place of kosher salt for seasoning meat by hand	Use less and sprinkle from a height, then taste	Method

How these were worked out. By weight: the Codex standard requires food-grade salt to be at least 97% sodium chloride on a dry basis, not counting additives.¹¹ By volume: the kosher-to-table amounts reverse the conversions above (1 ÷ 1¼ is ⅘ and 1 ÷ 2 is ½), rounded down so you start low. In baking, where salt has to disperse through a dough and is often measured by the spoon, fine salt is the predictable choice; that is common practice rather than a tested rule.

Which to use when

Kosher salt: seasoning meat and vegetables by hand before cooking, where ATK’s testers prefer it;¹ brining poultry, which Morton suggests for its kosher salt.⁵
Table salt: anything measured by the spoon, and the shaker. Morton markets its iodized salt for cooking, baking and seasoning at the table.⁶

Using kosher salt at the table and fine salt in measured recipes is a sensible split, though it is kitchen judgment rather than a tested rule.

Health notes

Sodium. Weight for weight there is no difference: the AHA says table salt, kosher salt and most sea salts are about 40% sodium.² Per spoonful, kosher salt carries less. Morton’s labels give 480 mg of sodium per ¼ teaspoon of its kosher salt and 590 mg for its iodized table salt;⁵⁶ Tufts gives a teaspoon of kosher salt as 1,920 mg against 2,325 mg for table salt, without naming a brand.³ The FDA’s Daily Value for sodium is less than 2,300 mg a day, about a teaspoon of table salt.¹² Switching to kosher salt only lowers sodium if you end up using less salt by weight.
Iodine. This is a real difference. US iodized salt contains 45 mcg of iodine per gram, and iodization in the US is voluntary.⁷ The NIH Office of Dietary Supplements lists kosher salt among specialty salts that are not usually iodized.⁷ Most salt in the American diet comes from processed foods, which almost always use noniodized salt.⁷ If you cook only with kosher salt and rely on salt for iodine, keep iodized salt on hand too; see iodized vs. non-iodized salt.

What isn’t known

No laboratory analysis of either kosher brand was found. The Swiss government survey of 25 salts included one standard iodized table salt but reported no sodium figure for it, and did not include kosher salt.¹³
Diamond Crystal’s own weight per teaspoon could not be retrieved from its maker; the figures here are ATK’s.
No published test of how either salt dissolves or distributes on meat was found, beyond Tufts’ general statement that kosher salt dissolves more slowly.
No dated, sourced price comparison.

Kosher salt and table salt, the full profiles
Kosher salt substitutes
Kosher salt vs. sea salt, pickling salt vs. kosher salt, Maldon salt vs. kosher salt and fleur de sel vs. kosher salt
Himalayan salt vs. table salt, rock salt vs. table salt and Celtic sea salt vs. table salt
Cooking with kosher salt, the best salt for cooking and too much salt

Salt Types and Measurements, America’s Test Kitchen. americastestkitchen.com · Publication ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴
Sodium Sources: Where Does All That Sodium Come From?, American Heart Association, 2025. heart.org · Reference work ↩ ↩² ↩³ ↩⁴ ↩⁵
What’s the difference between kosher salt and other salt?, Tufts Health & Nutrition Letter, 2013 (updated 2019). nutritionletter.tufts.edu · Publication ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹
Kate Shannon Levine, The Best Kosher Salt, America’s Test Kitchen, 2019. americastestkitchen.com · Publication ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³
Morton Kosher Salt Flakes, product page, Morton Salt. mortonsalt.com · Merchant ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸
Morton Iodized Table Salt, product page, Morton Salt. mortonsalt.com · Merchant ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸
Iodine: Fact Sheet for Health Professionals, NIH Office of Dietary Supplements. ods.od.nih.gov · Regulator ↩ ↩² ↩³ ↩⁴ ↩⁵
21 CFR 100.155, Salt and iodized salt, Electronic Code of Federal Regulations. ecfr.gov · Regulator ↩
Eden Faithfull, The Wrong Brand of Kosher Salt Could Ruin Your Dinner, America’s Test Kitchen, 2022. americastestkitchen.com · Publication ↩ ↩²
Salt Conversion Chart, Morton Salt. mortonsalt.com · Merchant ↩
Standard for Food Grade Salt, CXS 150-1985 (rev. 2012), Codex Alimentarius. services.bis.gov.in · Standard ↩
Sodium in Your Diet, U.S. Food and Drug Administration. fda.gov · Regulator ↩
Esther Infanger and Max Haldimann, Report on the composition of prevalent salt varieties, Swiss Federal Food Safety and Veterinary Office, 2016. warwick.ac.uk · Regulator ↩

Kosher Salt vs. Table Salt: Grain, Additives and How to Convert Between Them