Winemaking Reference Tables and Conversion Charts
Lookup tables printed in full, with the formula behind each one and an explanation of where it stops being reliable. No calculators to load and nothing that requires JavaScript, so the numbers are readable on a phone in a cellar with no signal and quotable by anything that reads the page. Longer operational and compliance guides live under guides.
Available tables
| Table | Range covered | Answers |
|---|---|---|
| Brix to Potential Alcohol | 16.0 to 30.0 Brix in half degree steps | Specific gravity, sugar in grams per liter, and potential alcohol at both the 0.55 and 0.59 conversion factors |
| Molecular SO2 by pH | pH 2.90 to 4.00 in 0.05 steps | Free SO2 required to hold 0.5 mg/L molecular for reds and 0.8 mg/L for whites, at the pKa of 1.81 |
| Grape Tons to Cases | 1 to 500 tons | Gallons, cases, and bottles at 170 gallons per ton, plus the realistic range, and fixed conversions for barrels, hectoliters, and cases |
Constants used across these tables
| Constant | Value | Used for |
|---|---|---|
| Brix to alcohol conversion factor | 0.55 to 0.60 typical | Potential alcohol estimation |
| pKa of sulfur dioxide and bisulfite | 1.81 at 20 degrees Celsius | Molecular SO2 calculation |
| Wine gallons per ton of grapes | 170 planning standard, 150 to 180 realistic | Yield estimation |
| Gallons per standard case | 2.378 for twelve 750 ml bottles | Case to gallon conversion for reporting |
| Liters per US gallon | 3.785 | Metric conversion throughout |
Every one of these is a convention or an approximation rather than a law of nature, and each table says where its own number stops being trustworthy. A winery that records its own results for two vintages will have better figures than any of them.