How much salt do I add to my ferment?
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Multiply the weight by your salt percent. For a mash, that is the weight of the peppers and anything else going into the jar: 500 g of chopped peppers at 2.5 percent takes 12.5 g of salt. For a brine, decide first whether your percent means percent of the water or percent of the peppers and water together, because the same number gives two very different jars [2]. USDA-ARS researchers report that vegetable ferments typically run at 2 to 3 percent salt and recommend a set level between 2.0 and 2.5 percent [1]; how that applies to peppers is on how much salt to use. Enter your weights and method, and the calculator returns grams of salt and what that salt works out to under each convention.
Three ways makers state a salt percent
Recipes say "3 percent salt" as if everyone agreed on what it is a percent of. They do not. A 2014 thread on The Hot Pepper forum laid out the conventions makers actually use and found members split between them [2]. The calculator handles the three that are done by weight.
| Method | The percent is of | Salt in grams | Typical use |
|---|---|---|---|
| Mash (dry salting) | Peppers and other produce | produce weight × percent | Chopped or blended peppers salted directly, the usual way to make a pepper mash |
| Brine, total weight | Peppers plus water | (produce + water) × percent | Whole or sliced peppers covered with water, when you want the jar as a whole to land at a set salt level |
| Brine, water only | The water alone | water weight × percent | The "exclusive" brine most forum members in that thread mixed ahead and poured over the peppers [2] |
A fourth convention, salting by the combined volume of peppers and water, also appears in that thread [2]. The calculator does not offer it. A cup of sliced peppers holds a lot of air, and the weight of a "cup" changes with how you cut and pack them, so the answer would change from jar to jar.
Worked examples on the scale
A small mash
You have 500 g of stemmed, chopped peppers, garlic and onion, and want 2.5 percent salt.
500 × 0.025 = 12.5 g salt.
Weigh the produce after trimming, since stems and the bits you throw away are not in the jar. Mix the salt through evenly before packing.
Whole peppers under brine
You have 400 g of whole peppers in a jar that takes about 600 g of water to cover them, and you want the whole jar at 3 percent.
(400 + 600) × 0.03 = 30.0 g salt, dissolved in the 600 g of water.
The water you pour in is 30 ÷ 600 = 5.0 percent salt by the water-only convention. Once salt moves into the peppers and water moves out, the jar settles toward 3 percent overall. The easiest way to find your water weight is to pack the peppers, set the jar on a tared scale, fill it with plain water to where the brine will sit, and read the number.
Following someone else's brine recipe
A recipe says "use a 5 percent brine." If it means water only, the same jar of 400 g peppers and 600 g water takes 600 × 0.05 = 30.0 g of salt, which is the jar above, at 3.0 percent overall. If it means total weight, it takes 1,000 × 0.05 = 50.0 g, two thirds more salt. When a recipe does not say which, the calculator shows both answers so you can see how far apart they are before you choose.
Why the calculator shows the same salt three ways
Every result lists the salt as a percent of produce (for a mash), of produce plus water, and of water alone (for a brine), plus one more figure: salt as a share of everything in the jar, salt included. For the brine example that last figure is 30 ÷ 1,030 = 2.91 percent. The difference from 3.00 is small and nobody needs to chase it, but it explains why two careful people can describe the same jar with slightly different numbers.
The point of showing all of them is translation. If a tested recipe or a process authority gives you a number in one convention, you can match it exactly, whichever way you prefer to weigh. How much salt is right for flavor, speed and keeping surface growth down is a separate question, answered with the reasons on how much salt to use. The calculator flags anything above 5 percent for a second look. That threshold is an interface choice, well above the 2 to 3 percent range in the research [1]; what changes at 10 percent and above is explained on the salt page.
What happens to the salt in the finished sauce
Salt does not leave when the ferment is done. When you blend the mash with vinegar, fruit or water to finish it, the same grams of salt are spread through a bigger batch. Take the 500 g mash above (512.5 g with its salt) and blend in 150 g of vinegar: the finished sauce is 12.5 ÷ 662.5 = 1.89 percent salt. Drain off some brine from a whole-pepper ferment and you remove salt with it, so measure what you actually use.
For a sense of where finished sauces land, the USDA's purchasing specification for hot sauce allows salt from 1.2 to 12.0 percent depending on the style [3]. That range describes commercial products, and salt in this range is a flavor and specification number. It does not make a sauce shelf stable; acidity and the process do that, as what pH hot sauce needs to be explains. To track salt through a full recipe, put the finished formula into the recipe to formula calculator.
Weigh the salt, every time
Salt by the spoon is the most common reason a ferment comes out saltier or blander than planned. Fine table salt packs tightly; flaky kosher salt is mostly air; a tablespoon of one is not a tablespoon of the other. The calculator therefore gives grams and ounces and never teaspoons. For jars under a kilogram, a pocket scale that reads to 0.1 g makes the difference between 12 g and 13 g visible, and on a 500 g mash that is the difference between 2.4 and 2.6 percent. If you weigh in ounces, the calculator converts at 28.34952 g per ounce [4].
Which kinds of salt makers choose for ferments, and why, is on the salt page linked above.
Before you pack the jar
With the salt weighed, the method itself, from trimming through weighting the solids and checking pH, is on how to ferment peppers, step by step. If you are still deciding between a mash and whole peppers in brine, mash or brine compares flavor, speed and surface growth.
| Salt | 12.5 g (0.44 oz) |
|---|---|
| Salt percent | 2.50% |
| Percent of produce | 2.50% |
| Percent of everything including the salt | 2.44% |
References
- Snyder A, Breidt F, Andress EL, Ingham BH, Manufacture of Traditionally Fermented Vegetable Products: Best Practice for Small Businesses and Retail Food Establishments, Food Protection Trends 40(4):251-263, 2020. https://www.ars.usda.gov/ARSUserFiles/60702500/Fermented%20Veg%20Manuscripts/p437.pdf
- The Hot Pepper forum, "Some confusion about brine types," thread started September 24, 2014. https://thehotpepper.com/threads/some-confusion-about-brine-types.50399
- USDA Agricultural Marketing Service, Commercial Item Description A-A-20097G, Hot Sauce, July 12, 2019. https://www.ams.usda.gov/sites/default/files/media/AA20097GHotSauce.pdf
- Nebraska Department of Water, Energy, and Environment, "O" Conversion/Equivalency Factors, undated, accessed October 2026. https://dwee.nebraska.gov/state-energy-information/energy-statistics/miscellaneous/conversion-factors/o-conversionequivalency-factors
