Wine Chaptalisation Calculator

Work out wine chaptalisation instantly with clear inputs, formula shown and shareable results.

About Wine Chaptalisation Calculator

Potential alcohol is Brix times a conversion factor of 0.55-0.62 depending on yeast and fermentation conditions. Chaptalisation adds sugar to close the gap: roughly 1.05 kg of sugar per hectolitre per degree Brix, accounting for the volume the sugar itself occupies.

Formulas

Potential alcohol

Potential ABV % = Brix x conversion factor

Sugar addition

Sugar (kg) = must volume (L) x Brix deficit / 100 x 1.05

Worked example

With the default values below, Wine Chaptalisation Calculator returns Sugar To Add of 21.356. Change any input above and every figure here is recalculated in your browser.

Inputs used

Must Volumeminimum 0 L: 1,000 L
Current Sugar Levelaccepts 0–40 Bx: 20 Bx
Target Alcoholaccepts 0–20 %: 13 %
Brix To Alcohol Factoraccepts 0.3–0.8: 0.59

Results

Sugar To Add: 21.356
Potential Alcohol Before Addition: 11.800%
Brix Shortfall: 2.034
Alcohol Gained: 1.200%

Step by step

1Values used
2Potential alcohol
3Sugar addition
4Sugar To Add= 21.356
5Potential Alcohol Before Addition= 11.800
6Brix Shortfall= 2.034
7Alcohol Gained= 1.200

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 3 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
Enrichment of must is regulated and often prohibited or capped by wine law. Confirm the rules for your appellation before adding sugar.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Enrichment of must is regulated and often prohibited or capped by wine law. Confirm the rules for your appellation before adding sugar.

Frequently Asked Questions

Is chaptalisation legal everywhere?

No. It is permitted in some regions and prohibited or capped in others, particularly in warm-climate appellations. Maximum enrichment is usually limited to 1.5-3% ABV where allowed.

Does added sugar affect quality?

It raises alcohol without adding flavour or extract, so heavily chaptalised wines can taste thin and unbalanced. It is intended to correct a poor season, not to replace ripeness.