Calculator

Priming Sugar Calculator.

Calculate the priming-sugar dose for bottle conditioning beer. Six style-family presets set typical carbonation levels; six fermentables show their equivalent doses side-by-side. The calculation accounts for residual CO2 dissolved in the beer at packaging temperature.

Inputs

Enter beer volume, the highest temperature your beer reached since fermentation finished, and pick a target.

Volume going into the bottles (after racking).
Highest temp reached since fermentation completed.
Style families are Cellar Bench's own taxonomy. Pick "Custom" to set a value directly.
SugarDoseNotes
Corn sugar (dextrose)Calibrated default; flavour-neutral
Table sugar (sucrose)~10% less by mass than dextrose
Dry malt extract (DME)Adds slight malt character
Brown sugarLight caramel notes
HoneyBoil briefly first; flavour varies
Maple syrupMild maple character

How this is calculated.

Show the formula and citations

Residual CO2 already dissolved in the beer at temperature T (°F), per a Henry's Law fit:

V_residual = 3.0378 − 0.050062 × T_F + 0.00026555 × T_F²

Additional CO2 needed = target − residual.

Dextrose dose — 1 g of dextrose per litre of beer raises CO2 by ~0.25 volumes:

grams_dextrose = volume_L × (V_target − V_residual) × 4.0

Other fermentables scale relative to dextrose: sucrose × 0.91, DME × 1.51, brown sugar × 0.95, honey × 1.30, maple syrup × 1.45.

Sources: Fix, G. (1989). Principles of Brewing Science. Brewers Publications. White, C. & Zainasheff, J. (2010). Yeast. Cross-validated against Brewer's Friend priming-sugar calculator.

Worked example.

A pale ale, room-temp bottling

19 L beer · 20 °C / 68 °F · Target 2.4 vol (Hoppy Ales)

Residual CO2 at 68 °F: 3.0378 − 3.404 + 1.227 = 0.86 vol
Additional needed: 2.4 − 0.86 = 1.54 vol
Dextrose: 19 × 1.54 × 4.0 = 117 g (or 106 g sucrose)

Common mistakes.

  • Entering the cold-conditioned temperature. If your beer fermented at 20 °C and you cold-crashed to 4 °C before bottling, enter 20 °C — that determined the residual CO2. The cold temperature didn't suddenly add more.
  • Targeting wheat-beer carbonation in standard bottles. Above 4 vol, 12 oz crown caps and standard glass aren't rated for the pressure. Use champagne bottles and proper crowns or step the target down.
  • Skipping the boil for non-sugar fermentables. Honey, maple syrup, and DME need a brief boil to pasteurise before adding. Dextrose and sucrose dissolve clean from the bag.
  • Not mixing the priming solution into all the beer. Add the sugar solution to the bottling bucket first, then rack gently from the fermenter on top. Stirring in the bucket risks oxidation.

Related calculators.

Frequently asked.

Which beer temperature should I enter?

Enter the highest temperature your beer reached after fermentation finished — not the current cold-conditioned temperature. The higher temperature determines how much CO2 is already dissolved in the beer.

What's the difference between corn sugar and table sugar?

Corn sugar (dextrose) is the calibrated default — it carbonates predictably with no flavour contribution. Table sugar (sucrose) is about 10% more efficient by mass, so you use a bit less. Either works for bottle conditioning.

Is bottle conditioning safe at high carbonation levels?

Above roughly 4 volumes of CO2, you need pressure-rated bottles (champagne or Belgian-style) and crowns rated for the pressure. Standard 12 oz crown caps on standard glass are designed for around 3 vol. The calculator warns above 4.0 vol.

Can I use honey or maple syrup to prime?

Yes. Both work but contribute small amounts of flavour. They are less consistent than dextrose because their sugar content varies. Boil briefly to pasteurise before adding.