Free tools for winemakers
Blend to a target calculator
Mix two liquids to hit a target value — the Pearson square
Liquid B to add
- Liquid A
- Liquid B
Type both values, the target and the volume.
For values that mix by volume (% vol, g/L), not Brix, which is by weight.
Measure after blending. Spirit and wine shrink slightly when mixed, so the blend comes out a little stronger than calculated.
Blending more than two lots? Use the wine blending calculator.
How do we calculate this?
The exact formulas used in this tab:
What this calculator does
Works out how much of two liquids to mix so the blend lands on a target value — the Pearson square.
- Use it to fortify a wine with spirit, to sweeten with a sweeter wine, or to raise or lower acidity with another wine.
- Give the volume of one liquid to size the other, or a total volume to split between them.
The formula
a = liquid A, b = liquid B, t = targetRatio A : B = |b − t| : |t − a|I have this much A: B = A × (t − a) ÷ (b − t)I want this total V: A = V × (b − t) ÷ (b − a), B = V × (t − a) ÷ (b − a)For values that mix by volume (% vol, g/L), not Brix, which is by weight
Worked example
- 100 L of wine at 13 % vol
- Spirit: 96 % vol
- Target: 18 % vol
- Mix ratio, wine to spirit (96 − 18) : (18 − 13) = 78 : 5
- How much spirit 100 × 5 ÷ 78 = 6.41 L
- Blend in all 100 + 6.41 = 106.41 L
Add 6.41 L of spirit
The answer stays in the unit you typed: in gallons, the same blend gives 6.41 gal of spirit.
Questions
What is the Pearson square?
A quick way to find the mix ratio of two liquids. Each liquid’s share is the distance from the other liquid’s value to the target, as the “Ratio” line of the formula above shows. The calculator does that sum and turns the ratio into volumes.
Why doesn’t it work with Brix?
Brix is a share by weight, so it doesn’t mix in proportion to volume. Use values that do: alcohol in % vol, or sugar and acid in g/L. To blend musts by sugar, first convert each reading to g/L with the sugar converter.
Will the blend land exactly on the target?
Close, but not exactly. Spirit and wine shrink slightly when mixed: the blend ends up a little smaller than the two volumes added together, while the alcohol in it stays the same. So its strength comes out a little above the target. Measure after blending, and adjust if you need to.