Salt-amount formulas
Let W be water mass, F be food mass, S be salt mass and p be the numerical percentage, such as 3 for 3%.
Solution basis: S = W × p / (100 − p)
Food + water basis: S = (F + W) × p / 100
The food-plus-water convention excludes added salt from its denominator. The solution convention includes only salt and water. Percentages for salt-amount calculations must be greater than zero and less than 100.
Reverse calculations and scaling
Solution percentage: 100 × S / (W + S)
Food + water percentage: 100 × S / (F + W)
Reverse calculations accept zero salt. Water must be positive unless food is included and its combined mass with water is positive. Scaling multiplies each included ingredient by the same positive factor. Intermediate results are not rounded; displayed results are rounded for reading.
Unit factors
One kilogram equals 1,000 g, one pound equals 453.59237 g, and one weight ounce equals 28.349523125 g. Water volumes use 1 mL ≈ 1 g: one US cup = 236.5882365 mL, one US quart = 946.352946 mL and one US gallon = 3,785.411784 mL.
Displayed salt weights generally use two decimals. Small results may show additional decimals or scientific notation. Display precision is not a statement about the precision of your scale or the density approximation.
Limits of the model
The model includes water, plain salt and optional food mass. It does not include pre-existing salt, sugar, dissolved juices, salt uptake, evaporation, density changes or final brine volume. High-concentration calculations can exceed what dissolves; the tool does not model saturation.
A ratio does not establish process safety. For preservation, follow a tested recipe and its full treatment and storage instructions. Plain salt and nitrite curing salts are not interchangeable.
References and review
The arithmetic is derived from the definitions above. Oregon State University's Preparation of Salt Brines for the Fishing Industry discusses solution concentration, salometers and changes in volume. Its measurements are temperature-dependent.
The National Center for Home Food Preservation's General Information on Pickling explains tested ingredient proportions and distinctions between pickling and fermentation.
Formulas and unit conversions checked on October 5, 2026. Contact the site owner for corrections; this is not a claim of independent laboratory validation.