Use 3/4 teaspoon of table salt for every 1 teaspoon of Morton kosher salt a recipe calls for, and about 1/2 teaspoon for every 1 teaspoon of Diamond Crystal. The kosher salt to table salt conversion is not one number because the two kosher brands weigh differently, and a teaspoon measures volume, not salt. The reliable fix is a gram figure: a level teaspoon of table salt is 6 g, so match that weight whatever box you hold.
Morton prints the numbers on its own labels. A 1/4 tsp serving of Morton Coarse Kosher Salt is 1.2 g and 480 mg sodium; the same 1/4 tsp of Morton Iodized Salt is 1.5 g and 590 mg sodium. That 25% gap is the whole reason an American recipe written for kosher salt turns too salty when you spoon table salt in one-for-one. Keep the salt you actually use in one open jar by the range, such as the Houseland ceramic seasoning jar with its 3.2 in (8.2 cm) spoon, and write the brand on it so the maths never changes between batches.
The short answer
Halve or quarter-cut the volume, or weigh 6 g per teaspoon of table salt the recipe means. Morton's own conversion chart says 1 teaspoon of table salt equals 1 1/4 teaspoons of its coarse kosher salt, and 1 tablespoon of table salt equals 1 tablespoon plus 3/4 teaspoon of kosher. Run that backwards and 1 teaspoon of Morton kosher becomes 4/5 of a teaspoon of table salt, which most cooks round to 3/4.
Diamond Crystal is a different product. Wikipedia's kosher-salt entry notes that between brands "the same volume measure may contain twice as much salt (by mass)", and Diamond Crystal's hollow pyramid crystals sit at the light end. For a Diamond Crystal recipe, start at half the volume in table salt, taste at the end, and add pinches from there. A 5 mL teaspoon (the FDA labelling definition in 21 CFR 101.9) of any salt holds a fixed volume; what changes is how much air is packed between the grains.
Why does a teaspoon of kosher salt weigh less than a teaspoon of table salt?
Because the crystals are a different shape, so the same 5 mL spoon traps more air. Table salt is small, near-cubic grains that pack tight; solid sodium chloride has a density of 2.17 g/cm3, and table salt in a spoon comes to roughly 6 g per level teaspoon once the air gaps are counted. Kosher salt, per Wikipedia, has "a flat plate-like shape and for some brands may also have a hollow pyramidal shape", which stacks loosely.
The two big American brands make those shapes differently. Diamond Crystal is grown by the Alberger evaporation process into hollow pyramids; Morton pressure-rolls its grains into flat flakes. Morton's flakes are denser than Diamond Crystal's pyramids, which is why a Morton recipe needs a smaller correction than a Diamond Crystal one. The word kosher, by the way, describes the job: koshering meat by drawing out blood with coarse salt, which is why the grains are large enough to pick up with your fingers. That finger-pinch habit is the subject of why chefs salt from their fingers, and it is also why kosher salt users rarely notice the volume problem until they hand the recipe to someone with a shaker.
Which kosher salt to table salt conversion should you use?
Use the brand-specific row below, and weigh anything over a tablespoon. The table salt row is Morton Iodized at 1.5 g per 1/4 tsp; the Morton kosher row is its published 1.2 g per 1/4 tsp; the Diamond Crystal row is the halving rule from the density note above, so treat it as a starting point and read the gram weight on your own box.
| Recipe says | Weight of 1 tsp | Use this much table salt | Sodium in that amount |
|---|---|---|---|
| 1 tsp table salt (Morton Iodized) | 6 g | 1 tsp | 2,360 mg |
| 1 tsp Morton Coarse Kosher | 4.8 g | 3/4 tsp (0.8 tsp exact) | 1,920 mg |
| 1 tbsp Morton Coarse Kosher | 14.4 g | 2 1/2 tsp (2.4 tsp exact) | 5,760 mg |
| 1 tsp Diamond Crystal | about half of table salt | 1/2 tsp, then taste | read the label |
| 1 tsp Morton Fine Sea Salt | close to table salt | 1 tsp | close to 2,360 mg |
The sodium column is the sanity check. Every 1 g of salt from any of these boxes is about 390 mg sodium; Morton's label shows 590 mg in 1.5 g and 480 mg in 1.2 g, both within rounding of that figure. Salt is salt. The spoon lies, the gram does not. If a soup already went over, fixing a soup that is too salty covers dilution ratios that actually work.
How do you convert a recipe without a kitchen scale?
Cut the volume by the brand ratio, then hold back a quarter of it until the end. Salt can be added; it cannot be removed. The steps below cost 30 seconds and save the dish.
- Find the salt line and the brand. American recipes from 2010 onwards usually say "kosher salt"; a Diamond Crystal author often says so in the headnote. No brand named: assume Morton and use the 3/4 rule.
- Multiply. 2 tsp Morton kosher becomes 1 1/2 tsp table salt; 1 tbsp becomes 2 1/2 tsp; 2 tsp Diamond Crystal becomes 1 tsp table salt.
- Level the spoon. A 5 mL teaspoon scraped flat with a knife is the only measure the conversion is built on; a heaped teaspoon of table salt can carry 8 g or more.
- Add three quarters of the converted amount during cooking, the rest at the table after tasting. Brines and doughs are the exception: for those, weigh, because you cannot taste-correct a 1% brine or a bread dough after the fact.
- Write the working conversion on the salt jar. A strip of masking tape reading "Morton kosher, 4.8 g per tsp" beats redoing the maths every Sunday; how to write spice labels that last shows what ink survives a steamy stove.
The Houseland seasoning jar holds about 300 ml of salt, which is roughly 60 level teaspoons of table salt or 75 of Morton kosher at the weights above, so one fill covers a month of weeknight cooking and the label on the lid keeps the ratio in view.
From the shop
Salt Cellar With Spoon, Ceramic Seasoning Jar With Bamboo Lid
About 300 ml per jar with a 3.2 in (8.2 cm) spoon, so one fill is roughly 60 teaspoons of table salt kept dry under a bamboo flip lid. Hand wash only; the bamboo lid should be wiped, not soaked.
View the ceramic salt cellar — 3 set sizes & current priceDoes the salt taste different, and does iodine matter?
By weight they taste the same; the differences are speed of dissolving and what is added. A 6 g dose of kosher salt and a 6 g dose of table salt deliver the same 2,360 mg or so of sodium once dissolved. Large flakes dissolve slower, so a kosher-salt finish on a steak reads as bursts while table salt reads as an even wash. In a stew or a pot of pasta water the difference disappears within 2 minutes.
Iodine is the real nutrition gap. Morton Iodized Salt lists 45% of the daily value of iodine in a 1/4 tsp serving; Morton Coarse Kosher Salt is not iodized and Diamond Crystal, per Healthline, is free of additives entirely. Morton's FAQ also says table salt carries under 0.5% calcium silicate to keep it pouring and that plain salt "has no expiration date", while iodised salt can lose potency over time. Which means a household that cooks entirely from a kosher box gets its iodine from dairy, seafood or seaweed, not the salt shaker. Keep both salts in the kitchen if that matters to you: kosher in the open jar for cooking, iodised in a shaker for the table.
How should you store salt so the measure stays honest?
Dry, lidded, at counter height, and one brand per jar. Salt does not spoil, but damp salt clumps, and a clump-heavy teaspoon can weigh 20% more or less than a level one, which wrecks a conversion you did correctly. Morton's advice is a cool, dry spot away from the stove or an airtight container.
- Keep the cooking salt within arm's reach of the range in a jar with a lid that flips, so steam is not sitting on open salt while the pot boils. The Houseland ceramic seasoning jar is 4.1 in (10.5 cm) wide and 3.6 in high with a bamboo flip lid, sized for a pinch or the 3.2 in spoon.
- Never mix brands in the same jar. Half Morton, half Diamond Crystal gives a teaspoon nobody can convert.
- Hand wash the ceramic body and dry the bamboo lid rather than soaking it; wet bamboo plus salt residue is how a lid stains. The product page calls for hand washing, which is the trade-off against a dishwasher-safe glass jar.
- Refill from the box, not the shaker, and copy the gram-per-teaspoon figure from the nutrition panel onto the label each time you change brand.
Pantry stock can live in its box; the fold in salt keeper, crock, cellar or server explains why the counter jar is the one that matters. The rest of the kitchen and home collection follows the same idea: fewer things on the counter, each doing one job.
What I'd do
Buy a 0.1 g digital scale and stop converting altogether. Every recipe salt line becomes grams: 6 g per teaspoon of table salt, 4.8 g per teaspoon of Morton kosher, and whatever your Diamond Crystal box prints for a 1/4 tsp multiplied by four. For the days the scale is in a drawer, the 3/4 rule for Morton and the 1/2 rule for Diamond Crystal get you within a pinch, and a pinch at the table is a correction; a doubled dose in the pot is a ruined dinner.
Keep one salt in one jar with the ratio written on it. The 5 mL teaspoon is a fine tool for measuring water. For salt, it needs a footnote, and the footnote is the brand.
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