Lacto-fermentation, measured.
Salt math for fermentation, solved.
Weigh your cabbage, pepper mash or cucumbers in grams, pick a salt percentage, get the exact salt mass. No sign-up. No ads until you finish the math.
Salt calculator
Enter your vegetable weight and a salt percentage. We return the exact salt mass in grams, plus teaspoons for each common grain.
Grain matters: one teaspoon of Diamond Crystal weighs half as much as one teaspoon of fine sea salt. Weigh in grams when you can.
All salt grains
| Grain | Grams | Teaspoons | Tablespoons |
|---|---|---|---|
| Diamond Crystal kosher | 20 g | 7.04 | 2.35 |
| Morton kosher | 20 g | 4.17 | 1.39 |
| Fine sea salt | 20 g | 3.51 | 1.17 |
| Pickling / canning | 20 g | 3.64 | 1.21 |
Our methodology
We weight salinity over time-and-temperature when sources conflict. Home fermenters control salinity reliably; kitchen temperature less so. Percentages are always by weight (salt mass ÷ vegetable mass, or salt mass ÷ water mass), never by volume — teaspoons of Diamond Crystal weigh almost half what teaspoons of fine sea salt do, which is the most common cause of failed ferments. The 1.5% floor for dry-salt ferments and the 2.5% floor for submerged brines are enforced as safety verdicts, not hidden as warnings.
Data we cite on every page
Fermentcalc builds on the National Center for Home Food Preservation (NCHFP), the FDA pH-safety threshold (4.6), USDA canning guidance, Sandor Katz’s Wild Fermentation and Art of Fermentation, the Noma Guide to Fermentation by René Redzepi and David Zilber, and the Joy of Pickling by Linda Ziedrich. Every data-backed page names a source and a last-verified date.