Free tools
Winemaking calculators and bench methods
Calculators for the arithmetic of winemaking, and the bench methods behind the figures you put into them. They're free, and they need no account. Nothing you type here is saved.
Calculators
- Molecular SO₂ calculator
Work out the free SO₂ a wine needs at its own pH, and how much potassium metabisulfite or sulfite solution adds it, with the working shown.
- Acid adjustment calculator
Work out how much tartaric acid raises a wine's TA to your target, or how much potassium bicarbonate or calcium carbonate lowers it.
- Chaptalization and alcohol calculator
Work out the sugar that raises a must to a target Brix or the water that lowers it, the potential alcohol at each, and alcohol from gravity.
- Wine blending calculator
Work out how much of two wines to blend to reach a target alcohol, TA, residual sugar or VA, one measure at a time, by the Pearson square.
- Winemaking unit converter
Convert gallons and liters, ounces and grams, grams into ppm in a tank, and Fahrenheit and Celsius, both ways, with the factor shown.
- SO₂ and gravity tables
The free SO₂ that reaches each molecular target at each pH, and gravity beside Brix, sugar and potential alcohol, to read off at the bench.
Bench methods
- Total acidity, by titration
How to titrate a wine's total acidity to pH 8.2 with sodium hydroxide, and turn the burette reading into g/L as tartaric acid.
- Free SO₂, by titration
How to measure free SO₂ by the Ripper titration or by aeration-oxidation, why the two disagree on a red wine, and how to work out the ppm.
- Sulfite solution, by weight
How to make up a potassium metabisulfite solution by weight for SO₂ additions, and how much SO₂ each milliliter of it carries.
- Volatile acidity, by distillation
How to measure volatile acidity by steam distillation and titration, in g/L as acetic acid, and correct it for the SO₂ that distills over.
- Residual sugar, by copper reduction
How to measure the sugar left in a finished wine, by Clinitest tablets or the Rebelein copper titration, and why a hydrometer can't measure it.
- Malic acid, by chromatography
How to run a paper chromatography test for malolactic fermentation, and read the plate to tell a finished wine from one still going.
- Heat stability, by a heated sample
How to test a wine for protein haze: hold a filtered sample hot, cool it, and compare its turbidity with the same wine unheated.
- Cold stability, by freezer or conductivity
How to test a wine for tartrate crystals, by holding a sample in the freezer or by seeding it and watching its conductivity.