Getting the salt right is the difference between crisp, tangy ferments and a spoiled jar. This fermentation brine calculator works out exactly how much salt you need for any batch, whether you are making a submerged brine for pickles or salting shredded cabbage for sauerkraut. Set your water or vegetable weight, pick a salt strength, and it does the maths in grams and spoons.
Fermentation Brine Calculator
Use non-iodized salt (sea, pickling or kosher) and non-chlorinated water, and keep everything under the brine. Values are a starting point, adjust to taste. Coarse or kosher salt weighs less per spoon, so weigh it when you can.
How much salt should I use?
There are two ways to salt a ferment, and the calculator covers both:
- Brine (submerged vegetables) - for whole or chunky veg kept under liquid, like cucumbers, cabbage leaves or radishes. Salt is a percentage of the water weight. One litre of water weighs 1000 g, so a 5% brine is 50 g of salt.
- Salt by weight (kraut and kimchi) - for shredded or mashed veg that makes its own brine, like sauerkraut or kimchi. Salt is a percentage of the vegetable weight, usually 2 to 2.5%.
- Dill pickles (ogorki kiszone): a 4 to 5% brine. Try my Polish fermented dill pickles.
- Sauerkraut: 2% salt by cabbage weight.
- Kimchi: brine the vegetables at about 5%, then season the paste. See my cucumber kimchi and vacuum-bag kimchi method.
- Beetroot kvass: a light 2% brine. Here is my beetroot kvass.
Tips for a safe ferment
- Stay at 2% salt or higher. Below that, spoilage bacteria can get ahead of the good lactic acid bacteria.
- Use non-iodized salt (sea salt, pickling salt or kosher salt). Iodine and anti-caking agents can slow fermentation.
- Use non-chlorinated water. Filter tap water or leave it out overnight so the chlorine escapes.
- Keep everything under the brine with a weight. Anything above the surface can grow mould.
What You’ll Need for Fermenting
A handful of basics make fermenting simple and safe. These are the tools I actually reach for in my own kitchen.
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FAQ
What percentage of salt do I need to ferment vegetables?
Most vegetable ferments sit between 2% and 5%. Shredded ferments like sauerkraut and kimchi use about 2 to 2.5% of the vegetable weight, while submerged pickles use a 4 to 5% brine. Staying at 2% or above keeps the ferment safe while the good bacteria take over.
Should I measure salt by weight or by spoons?
By weight whenever you can. A tablespoon of fine sea salt weighs far more than a tablespoon of flaky or coarse kosher salt, so spoons are only a rough guide. The calculator shows grams first and gives an approximate spoon count for fine sea salt.
Can I make my ferment less salty?
You can go as low as 2% for a milder result, but do not go under it for long ferments. If you want less salty pickles, ferment a little faster in a warmer spot and move the jar to the fridge as soon as they taste right.