You can use soy sauce instead of table salt at a ratio of 1 tbsp soy sauce per 1 tsp salt, minus 1 tbsp other liquid. Salt swaps are not about the saltiness of the salt — all salt is sodium chloride — they are about the size and shape of the crystals, and that is where most people go wrong. Salts differ by crystal size, so swap by weight, not by volume — kosher salt is far lighter per cup than table salt. A teaspoon of fine table salt packs far more salt into the spoon than a teaspoon of big, hollow kosher flakes, so a cup-for-cup swap can easily double the salt or halve it. The ratio above is the sourced ratio for this pair, and the table below scales it to the amounts recipes actually call for.
This matters more than it sounds. Salt is the one ingredient in almost every recipe, and it is the one where a small measuring error is immediately obvious: too little and the dish tastes flat, too much and it is inedible. That is why this guide spends time on weighing. A kitchen scale removes the whole problem — the same weight of any salt is the same amount of salt, whatever the crystal size. If you cook with more than one kind of salt, a scale is the single best purchase you can make, and it costs less than a bag of good flaky salt.
The ratio, in a table
| Table salt called for | Soy sauce | Other liquid to remove |
|---|---|---|
| 1/2 tsp | 1 1/2 tsp | 1 1/2 tsp |
| 1 tsp | 1 tbsp | 1 tbsp |
| 2 tsp | 2 tbsp | 2 tbsp |
| 1 tbsp | 3 tbsp | 3 tbsp |
The numbers in the table are the ratio 1 tbsp soy sauce per 1 tsp salt, minus 1 tbsp other liquid scaled up and down. All amounts in this guide are approximate, and the ratio comes from CookScale's substitution data rather than from a single brand's packaging. If the recipe matters — a cake for a celebration, a batch you are selling, or anything where a small error shows — weigh the ingredients on a kitchen scale and taste as you go. If you are in doubt, undershoot: add two-thirds of the salt, taste, and add the rest. You can always add more salt at the end of cooking, but you cannot take it out, and an over-salted pot is a much bigger problem than an under-salted one.
Worked examples
Example 1: A stir-fry that needs salt and depth
A stir-fry recipe calls for 1 teaspoon of salt. Use 1 tablespoon of soy sauce instead, and remove 1 tablespoon of other liquid from the recipe so the pan does not get watery. The soy sauce seasons the dish and adds a savoury, umami depth that plain salt cannot give, which is why this swap is an improvement in a stir-fry rather than just a substitute. Add the soy sauce when the vegetables are nearly done, so it coats them rather than boiling away.
Example 2: A soup that tastes flat
A soup recipe calls for 2 teaspoons of salt. Use 2 tablespoons of soy sauce instead, and remove 2 tablespoons of the stock. The soup will be seasoned the same, but it will also gain a savoury richness that makes it taste like it has been simmering for hours. Taste before serving: soy sauce varies in saltiness by brand, so the soup may need a little more, or a little less, than the ratio suggests. Add the soy sauce near the end of cooking so its flavour stays bright.
Example 3: A marinade for grilled chicken
A marinade recipe calls for 1 tablespoon of salt. Use 3 tablespoons of soy sauce instead, and remove 3 tablespoons of the other liquid in the marinade. The soy sauce seasons the chicken and adds colour and savoury depth, so the chicken will come off the grill browner and more flavourful than a salt-only marinade would give. Marinate for at least thirty minutes and no more than a few hours, so the salt does not start to cure the surface of the meat.
What changes in the result
The flavour change is the point of this swap: soy sauce is not just salty, it is savoury. It brings umami, a faint sweetness, and a dark colour that plain salt cannot give, so a dish made with soy sauce tastes deeper and more complex than the same dish made with salt alone. That is an advantage in a stir-fry, a soup or a marinade, and a problem in a pale sauce or a delicate dish where the colour and the flavour would be out of place. The liquid change matters too: a tablespoon of soy sauce is a tablespoon of liquid, so you must remove the same amount of other liquid, or the dish will be wetter than the recipe intended.
Texture changes too, in ways that have nothing to do with saltiness. Fine salt dissolves quickly and disappears into a sauce or a dough; coarse flakes dissolve slowly and can leave crunchy pockets if they are added late. Flaky salt sprinkled on top of a finished dish stays crunchy and gives little bursts of salt — that is its whole appeal. Kosher salt is the cook's favourite for seasoning by hand because the big crystals are easy to pinch and scatter evenly, and you can see where it has landed. None of this changes the flavour of the salt itself, but it changes how the dish eats, and that is what the cook is really choosing.
When not to substitute
Do not swap salts cup-for-cup; Diamond Crystal kosher salt is about half the weight of table salt per cup. Do not use soy sauce in a pale dish where its colour would show — a white sauce, a cream soup, a light-coloured dough — because it will tint the dish brown. Do not use it in baking, where the liquid and the flavour do not belong. And do not use it if anyone eating has a soy or wheat allergy, which is common and serious.
There are also jobs where one salt is simply the wrong tool. Do not use a coarse salt in a recipe where it has to dissolve quickly and completely — a smooth sauce, a meringue, a brine that needs to be exact — unless you give it time and stirring. Do not use a flavoured salt, like the celery salt in this guide's family, where the extra flavour would clash: it is a seasoning in its own right, not a neutral stand-in. And do not use an expensive finishing salt inside a dough or a stew, where its crunch and its delicate flavour disappear entirely. Save the good salt for the top of the dish, where you can taste it.
Practical guidance
Keep one salt as your everyday cooking salt and learn its measure by feel — most cooks use kosher salt for that, because it is easy to pinch and forgiving to scatter. Keep a small dish of flaky salt by the stove for finishing, and keep table salt for baking, where its fine crystals dissolve evenly and its exact measure matters. Label your containers, because kosher salt and table salt look similar in a jar and they are not interchangeable by the spoonful. When a recipe just says 'salt' with no kind given, it usually means table salt in older books and kosher salt in newer ones — if the result tastes under-salted, the recipe probably meant the finer salt, and if it tastes over-salted, it probably meant the coarser one. Taste as you cook, salt in stages rather than all at once, and remember that sauces and soups concentrate as they reduce, so the salt you add at the start tastes stronger by the end.
Soy sauce varies in saltiness by brand and by type — light soy sauce is saltier than dark, and Japanese shoyu is different again from Chinese light soy — so taste as you go rather than trusting the ratio blindly. Keep the bottle in the fridge once opened, and use it within a few months: it does not go off quickly, but it loses its brightness over time.
Frequently asked questions
Can I use soy sauce instead of salt in any recipe?
No — only in savoury cooking where its flavour and colour belong. It is excellent in stir-fries, soups, marinades and noodle dishes, and it is wrong in baking, in pale sauces, and in any dish where a dark colour would look odd. The ratio is 1 tablespoon of soy sauce per teaspoon of salt, and you must remove a tablespoon of other liquid for every tablespoon of soy sauce you add.
Is soy sauce saltier than salt?
By weight, no — salt is pure sodium chloride, while soy sauce is mostly water with salt dissolved in it. A tablespoon of soy sauce contains roughly the salt of a teaspoon of table salt, which is why the ratio is 1 tablespoon per teaspoon. The difference is that soy sauce also brings umami, sweetness and colour, so it tastes saltier and more complex than its sodium content alone would suggest.
Can I just swap salts 1:1 by volume?
Only if the two salts have similar crystal sizes. Fine sea salt and table salt are close enough for most cooking, and the ratio for this pair is 1 tbsp soy sauce per 1 tsp salt, minus 1 tbsp other liquid. But kosher salt and flaky salt are much lighter per spoonful, so a 1:1 volume swap under-salts the dish — sometimes by half. The safe rule is to swap by weight: the same weight of any salt is the same amount of salt, whatever it looks like.
Why do recipes specify a brand of kosher salt?
Because the two big brands are different densities. Diamond Crystal kosher salt is light and hollow, Morton is denser and heavier, so a teaspoon of one is not a teaspoon of the other. A recipe written for Diamond Crystal needs about one and a half teaspoons per teaspoon of table salt, while Morton needs about one and a quarter. If a recipe does not say which brand, Diamond Crystal is the usual assumption in American recipes.
Does the kind of salt change the flavour?
Barely, once it is dissolved. All salt is sodium chloride, and dissolved in a soup or a dough the differences are tiny. What changes is texture — flakes stay crunchy on top of a dish — and the trace minerals in some sea salts, which can add a very faint bitterness or sweetness that most people cannot detect in a finished dish. Choose salt for its crystal size and how you use it, not for a flavour difference you probably cannot taste.