Wine Blending Calculator
Calculate the blend ratio of two wines to hit a target Brix or total acidity.
Enter the properties of each wine and your desired blend target.
The Pearson square — the classic blending tool
Winemakers and dairy makers have used the Pearson square for over a century. It is just linear interpolation drawn as a diagram, but it answers the everyday question: how do I mix wine A (sugar/acid/alcohol value V_A) with wine B (value V_B) to land on target T?
fraction_of_A = (T − V_B) ÷ (V_A − V_B)
fraction_of_B = 1 − fraction_of_A
Wine A at 24 Brix blended with Wine B at 18 Brix to hit 21 Brix target: fraction_A = (21 − 18) ÷ (24 − 18) = 0.5. Half and half. For a 50 L batch, 25 L of each.
This works perfectly for any property that mixes linearly — Brix, titratable acidity in g/L, alcohol percentage, residual sugar in g/L, free SO2 in mg/L. It does not work for pH (which is logarithmic — see below).
What blends linearly and what does not
| Property | Linear? | Notes |
|---|---|---|
| Brix / sugar | Yes | Direct concentration math |
| Titratable acidity (TA) | Yes (close enough) | g/L additive within ±5% |
| Alcohol % v/v | Yes | Volume-weighted average |
| Residual sugar (g/L) | Yes | Additive |
| pH | No | Logarithmic; predict TA blend then measure pH |
| Tannin (perceived) | No | Non-additive, palate-driven |
| Colour intensity | Close to linear | Useful for rosé blending |
| Volatile acidity | Yes (g/L) | But often diluted away as a fault |
Why blend in the first place
- Fix imbalance. A high-Brix Cabernet at 25.5° (too hot) blended with a co-fermented Petit Verdot at 22° brings the final wine into balance without bleeding off must.
- Add complexity. Bordeaux blends, Châteauneuf-du-Pape blends, classic Rhône red and Champagne assemblage are all about layering different varieties.
- Hide a flaw. A wine with mild reduction can be blended away in small percentages. A wine with VA over 0.9 g/L cannot really be saved by blending — it just contaminates the blending partner.
- Hit a target. Commercial wineries blend across tanks to land on a consistent house style year after year. Same vintage, same label, similar mouthfeel.
The bench trial rule
Never blend on math alone. Run bench trials with 100 mL samples first: blend the calculated ratio, taste, then try 5% in each direction. The math gets you close; the palate decides what actually goes in the tank. The number the calculator gives you is a starting point, not a finished recipe.
The 85% varietal rule
Many wine regions require at least 85% of a single variety to label the wine by that variety. If you are blending to hit a Brix target but want to keep the “Cabernet Sauvignon” label, the maths has to live within that 85% limit. Check your local regulations — Old World, New World, and AVA rules all differ.