Using the free wine calculators
MakeWine's chemistry calculators are completely free and need no account — just open makewine.app/calculators in any browser. If you're signed in, they also live under Tools → 🧪 Calculators.
What's available
| Calculator | What it does |
|---|---|
| 🧪 SO₂ Addition | Work out sulphite additions to hit a target free SO₂ |
| 🍋 Acid Adjustment | Raise or lower titratable acidity |
| 🍬 Sugar / Chaptalization | Sugar needed to reach a target gravity or ABV |
| 💊 Campden Tablets | Convert tablets to ppm SO₂ for your volume |
| 🍾 ABV Calculator | Alcohol by volume from gravity readings |
| 💧 Dilution | Water additions and their effect on gravity and acid |
| 🌱 YAN / Nutrients | Yeast assimilable nitrogen and nutrient dosing |
| 🍯 Backsweetening | Sweeten a finished wine safely |
Each calculator page also links to related calculators, so you can move from a sugar addition straight to a nutrient plan.
Worked example: calculating ABV
Say you pitched a must at 1.090 and it has fermented dry to 0.995.
- Open the calculators page and choose ABV Calculator.
- Leave the Gravity unit as Specific Gravity (SG) — or switch to Brix (°Bx) if you measured with a refractometer.
- Enter Original gravity (OG):
1.090. - Enter Final gravity (FG):
0.995. - The results appear instantly, no button to press:
| Result | Value |
|---|---|
| ABV (wine) | 12.77% |
| ABV (simple) | 12.47% |
| ABV (Hall — beer) | 13.22% |
| Attenuation | 105.6% |
ABV (wine) is the figure to quote. It uses Duncan & Acton's formula, which was derived for wine and stays honest at dry finishing gravities like this 0.995.
The simple formula, (OG − FG) × 131.25, is the everyday shorthand and lands within about half a percent here.
Hall's formula is shown for comparison because it's the one most homebrew calculators use — usually mislabelled as "Balling". It was fitted to beer, which rarely finishes below ~1.008, so it over-reads on a dry wine: 13.22% against 12.77%. That 0.45% gap is the formula being used outside its range, not a more precise answer.
Attenuation above 100% simply means the wine finished below 1.000, which is normal for a dry wine.
Tips
- Every input shows a hint with a typical value (e.g. "Dry wine ≈ 0.990–1.000"), so you can spot a mistyped reading at a glance.
- The backsweetening calculator includes a stabilisation warning — always add sorbate and sulphite before sweetening a finished wine.
- Calculators are stateless and private: nothing you type is stored or sent anywhere.
Keep the numbers with your wine
The calculators are free forever, whether or not you register. When you want your readings and additions saved against an actual wine — gravity history, SO₂ additions, lab readings — create a free Cellar Hand account and log them on the wine's Additions log and 🔬 Lab tabs. See the "Getting started" tutorial for a walkthrough.