Wine Calculatorv1.0.0

This wine calculator combines five essential winemaking calculations into a single tool. Select a calculation mode using the radio buttons at the top, enter your values, and view results instantly. All inputs support decimal numbers and fractions such as 3/4 or 5 1/2. Results update automatically as you type, or you can press the Calculate button manually. Press Reset to clear all values and restore defaults across every section.

• Select Sugar and ABV to convert between Brix, Specific Gravity, and Plato scales. Enter a reading in any scale and the tool converts to all three while estimating potential alcohol by volume. The conversion uses the standard polynomial relationship: SG = 1 + (Brix / (258.6 - (Brix * 227.1 / 258.2))). Potential ABV is estimated using the formula (OG - FG) * 131.25, where FG is assumed to be 0.990 for a dry fermentation.
• Select Chaptalization to calculate sugar additions. Enter your must volume, current Brix, and target Brix. Choose between table sugar (sucrose) or honey. The tool calculates the weight of sugar needed using the formula: sugar (grams) = volume (liters) * (target Brix - current Brix) * density * 10, adjusted by the sugar type factor (1.0 for sucrose, 1.25 for honey due to its lower fermentable sugar content of approximately 80%).
• Select Sulfite / SO2 to determine potassium metabisulfite (K-meta) or Campden tablet additions. Enter the wine volume, current and target free SO2 levels in ppm, and the wine pH. The calculator determines the SO2 needed as: mg K-meta = volume (liters) * (target SO2 - current SO2) / 0.5725, where 0.5725 accounts for K-meta being 57.25% SO2 by weight. Campden tablet equivalents use 0.44 grams K-meta per tablet.
• Select Acid Adjustment to calculate how much tartaric, citric, or malic acid to add. Enter the wine volume, current titratable acidity (TA), and target TA in grams per liter. The formula is: acid (grams) = volume (liters) * (target TA - current TA). Different acid types produce different flavor profiles, so choose based on the wine style.
• Select Blending to estimate the properties of a blend from two wines. Enter the volume, ABV, TA, and pH for each wine. The tool calculates weighted averages for ABV and TA, and an approximate weighted average for pH. Note that pH blending is nonlinear in practice, so the result is an approximation.
• Open Settings to adjust the number of decimal places displayed or to enable step-by-step formula breakdowns for each calculation.

This calculator addresses the most common measurements and adjustments encountered during home winemaking, from initial must analysis through final blending. Each mode targets a specific stage of the process.

• Harvest Assessment: Measure grape must at harvest with a refractometer reading of 23.5 Brix and instantly see the equivalent Specific Gravity of 1.099 and a potential ABV of approximately 13.0%. Compare readings across multiple grape lots to decide which to blend or ferment separately.
• Must Correction: Determine that a cool-climate Riesling must reading 18 Brix needs 327 grams of table sugar per 20 liters to reach 24 Brix for a target ABV of 13.2%. Plan sugar additions before fermentation begins.
• Sulfite Management: Add the correct amount of potassium metabisulfite after malolactic fermentation. Enter a current free SO2 of 5 ppm, a target of 35 ppm at pH 3.4, and learn you need approximately 1.05 grams of K-meta per liter, or about 48 Campden tablets for a 20-liter batch.
• Acid Balancing: Adjust a flat-tasting Merlot with a TA of 4.5 g/L up to 6.5 g/L by adding 40 grams of tartaric acid to a 20-liter batch. Compare the amounts needed if using citric or malic acid instead.
• Blending Trials: Evaluate a 60/40 blend of a high-acid Cabernet (TA 7.0 g/L, ABV 14%) with a softer Merlot (TA 5.5 g/L, ABV 12%) to predict the blended result before committing to the full batch. Adjust volumes until the target profile is reached.
• Education: Study the relationships between Brix, Specific Gravity, and Plato scales side by side. Enable the step-by-step formula display to follow each conversion and understand the underlying math.
• Record Keeping: Bookmark a pre-filled URL with query parameters to save a specific calculation for future reference or to share with a winemaking partner.