Priming Sugar Calculator

How Priming Sugar Works

When you bottle beer, you add a small amount of sugar to the flat beer before capping. The residual yeast in the beer consumes this sugar, producing CO2. Since the bottle is sealed, the CO2 dissolves into the beer, carbonating it naturally.

Residual CO2

Your beer already has some dissolved CO2 from fermentation. The amount depends on the temperature: colder beer retains more CO2. This calculator accounts for the residual CO2, so you only add enough sugar to reach your target carbonation level.

The residual CO2 is calculated using the formula:

CO2 (vols) = 3.0378 - 0.050062×T + 0.00026555×T²

Where T is temperature in °F.

Sugar Types Compared

• Corn Sugar (Dextrose): The standard choice. It's a simple monosaccharide that ferments completely and cleanly. Factor: 1.0x
• Table Sugar (Sucrose): Slightly more efficient than corn sugar because it's denser per gram. Factor: 0.91x (you need 91% as much)
• DME (Dry Malt Extract): Produces a slightly fuller body and head. Less fermentable than pure sugar, so you need more. Factor: 1.46x
• Honey: Adds subtle flavor. Variable fermentability based on source. Factor: 1.22x

CO2 Volumes by Beer Style

• British Ales: 1.5-2.3 volumes (lower carbonation, smooth)
• American Ales/IPAs: 2.2-2.7 volumes (moderate)
• Lagers/Pilsners: 2.4-2.8 volumes (crisp)
• German Wheat: 3.0-4.0 volumes (highly carbonated)
• Belgian Ales: 3.0-4.5 volumes (very effervescent)

Safety Tips

• Never exceed 4.5 volumes of CO2 in standard glass bottles — this risks bottle bombs
• Make sure fermentation is truly complete before bottling
• Dissolve priming sugar in boiled water before adding to beer
• Stir gently to distribute sugar evenly without introducing oxygen
• Use a bottling bucket for even distribution rather than adding sugar to individual bottles