Free Tool

Salt Calculator

Input your vegetable weight. Get exact grams of salt for any brine percentage. No guessing, no conversion charts, no tablespoon nonsense.

Brine percentage
2.5%

Salt needed

—

grams

Brine concentration

2.5%

by weight

How fermentation salt percentage works

Salt percentage in fermentation is measured by weight, not volume. A tablespoon of fine salt weighs ~18g. A tablespoon of coarse salt weighs ~15g. Same volume, different results. That's why volume measurements are unreliable and why every recipe on SourChad uses grams.

The formula: salt (g) = total weight (g) × percentage / 100. For 600g of vegetables + water at 2.5%, you need exactly 15g of salt.

Salt percentage by recipe

Sauerkraut

Dry salt method, no added water

2%

Fermented Garlic

Standard brine, 4-week ferment

2.5%

Fermented Cucumbers

Higher salt keeps crunch

3–5%

Fermented Hot Sauce

Higher salt for pepper ferments

3–5%

Kimchi

Varies by recipe tradition

2.5–3.5%

Fermented Red Onions

Quick ferment, lower salt

2–2.5%

Frequently asked questions

Why measure salt by weight instead of volume?

Different salt types have different crystal sizes. A tablespoon of fine salt weighs ~18g, while coarse salt weighs ~15g. By weight, 15g is always 15g regardless of crystal size. This is why every professional fermenter uses a gram scale.

What happens if I use too little salt?

Below 2%, you risk spoilage bacteria outcompeting Lactobacillus. The ferment may develop off-flavors, become slimy, or grow mold. A 2024 study (PMID: 38717160) confirmed that proper salt concentration is essential for pathogen elimination.

What happens if I use too much salt?

Above 5%, fermentation slows dramatically. The Lactobacillus can still work, but it takes much longer. The result will be very salty. Most vegetables are best at 2–3%.

Should I use iodized salt for fermentation?

No. Iodine can inhibit Lactobacillus growth. Use non-iodized sea salt, kosher salt, or pickling salt. Avoid table salt with anti-caking agents.

Do I weigh the vegetables or the total brine?

It depends on the method. For brine ferments (garlic, cucumbers), weigh the total: vegetables + water. For dry-salt ferments (sauerkraut), weigh just the vegetables. This calculator handles brine ferments.

Related tools

pH Safety Check

Is your ferment safe? Check the pH.

Brine Calculator

Pick a jar size, get exact measurements.

Source: PMID: 38717160 — proper salt concentration combined with pH below 4.4 eliminates pathogen survival in fermented vegetables. Int J Food Microbiol, 2024.