Priming Sugar Calculator
Calculate how much priming sugar to add for bottle carbonation.
Enter batch size, desired CO2 volumes, beer temperature, and sugar type.
Priming Sugar Needed
Priming sugar is the small amount of fermentable sugar added at bottling to create natural carbonation inside the bottle. The yeast consumes it and produces CO2, which dissolves into the beer under pressure.
The Formula:
Sugar (grams) = (Volume of beer in liters) × (Target CO2 volumes − Current CO2 volumes) × 4.0 (for table sugar)
The factor changes by sugar type:
- Table sugar (sucrose): factor = 4.0 g/L per volume CO2
- Corn sugar (dextrose): factor = 4.5 g/L (less fermentable by weight)
- Dry malt extract (DME): factor = 8.0 g/L
Current CO2 is estimated from your fermentation temperature — beer retains dissolved CO2 based on the highest temperature it reached during fermentation.
| Fermentation Temp | Residual CO2 (volumes) |
|---|---|
| 18 °C (64 °F) | 0.85 |
| 20 °C (68 °F) | 0.79 |
| 22 °C (72 °F) | 0.74 |
Worked Example:
- Batch size: 19 liters
- Target carbonation: 2.4 volumes (typical American ale)
- Fermentation temp: 20 °C → residual CO2 = 0.79 volumes
- Using table sugar
Sugar = 19 × (2.4 − 0.79) × 4.0 = 19 × 1.61 × 4.0 = 122 grams
Practical Tips:
- Dissolve sugar in ~250 mL of boiled, cooled water before adding to the bottling bucket
- Stir gently — avoid splashing, which oxidizes the beer
- Condition bottles at 18–22 °C for at least 2 weeks before chilling
- Lagers and wheat beers often target 2.6–3.0 volumes; English ales prefer 1.5–2.0 volumes