Fermentation salt calculator
One standard, every time: salt as a percentage of total weight. Tell it what you’re fermenting and it does the math — in grams, ounces, and teaspoons for your exact salt.
What are you salting?
Salt type
Add to your Cabbage
25 g
of sea salt
≈ 4 tsp
Mix thoroughly into your shredded cabbage and massage until liquid releases.
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How much salt for fermentation?
The short version: weigh what you’re fermenting, pick a percentage, and multiply. Salt in grams = weight in grams × percent ÷ 100. For dry-salt ferments like sauerkraut, that’s a percentage of the vegetable weight. For a brine, it’s a percentage of the water weight (1 ml of water weighs about 1 gram).
A quick salt-percentage cheat sheet
- 2% — light and quick, milder flavor, ferments faster.
- 2.5% — the sauerkraut consensus. If in doubt, start here.
- 3–5% — brined pickles and firmer veg; keeps things crunchier.
- 5%+ — hot-pepper mash and long-term storage.
Does the type of salt matter?
For the ferment itself, weigh your salt and the brand barely matters — avoid table salt with anti-caking agents or iodine if you can, but grams are grams. Where it bites you is spoons: a teaspoon of Diamond Crystal kosher weighs far less than a teaspoon of Morton or pickling salt. That’s why this calculator gives you grams first and a teaspoon estimate second — pick your salt type above and the teaspoons adjust.
Common questions
Is there a free salt calculator for fermentation?
Yes — this page is a free fermentation salt and brine calculator, with no app or sign-up required. Enter the weight of your vegetables (or the water, for a brine) and a salt percentage, and it gives you the exact salt in grams, ounces, and teaspoons, including conversions for Diamond Crystal, Morton, pickling, and sea salt.
How much salt do I need for sauerkraut?
The widely used standard is 2.5% of the cabbage's weight. For 1000 g of cabbage that's 25 g of salt. Lower (around 2%) ferments faster and tastes milder; higher (up to about 3%) is firmer and slower. The National Center for Home Food Preservation's sauerkraut method uses a similar low-salt ratio.
How do I calculate a fermentation brine?
For a brine, take the percentage of the water's weight, since 1 ml of water weighs about 1 gram. A 3% brine is 30 g of salt per 1000 ml (1 liter) of water. Brined pickles and firmer vegetables usually sit in the 3–5% range.
What salt percentage is safe for fermenting vegetables?
Most lacto-fermented vegetables fall between 2% and 5% salt. Salt slows spoilage organisms while lactic-acid bacteria acidify the ferment; staying in this range and keeping everything submerged under the brine is what keeps a batch safe. When in doubt, 2.5% is a reliable starting point.
Does the type of salt matter?
By weight, no — grams are grams, so weigh your salt rather than measuring by spoon. Avoid table salt with iodine or anti-caking agents, which can cloud the brine or inhibit fermentation. Teaspoon volumes differ a lot between brands (Diamond Crystal weighs far less per teaspoon than Morton or pickling salt), which is why this calculator gives grams first.
Salt and safety guidance cross-checked against the National Center for Home Food Preservation.