Beer Priming Calculator
Calculates how much priming sugar to add at bottling time for home brewed beer. Includes the residual amount of CO2 present in the beer due to fermentation. Works for Corn Sugar (Dextrose), Table Sugar (Sucrose), and Dry Malt Extract (DME). Also known as bottle priming. Sugar is added at bottling time. The remaining yeast ferment the sugar and this produces CO2.

 Priming Calculator: Units: US - Gallons / F / Ounces Metric - Liters / C / Grams Amount Being Packaged: (Gallons) Volumes of CO2: (see table below) Temperature of Beer: (F) (see below *) CO2 in Beer: - Priming Sugar Options: - (Use one of the above options)
Carbonation Guidelines by Style
 British Style Ales 1.5 - 2.0 volumes Belgian Ales 1.9 - 2.4 volumes American Ales and Lager 2.2 - 2.7 volumes Fruit Lambic 3.0 - 4.5 volumes Porter, Stout 1.7 - 2.3 volumes European Lagers 2.2 - 2.7 volumes Lambic 2.4 - 2.8 volumes German Wheat Beer 3.3 - 4.5 volumes

* Temperature of Beer used for computing dissolved CO2:
The beer you are about to package already contains some CO2 since it is a naturally occurring byproduct of fermentation. The amount is temperature dependent. The temperature to enter is usually the fermentation temperature of the beer, but might also be the current temperature of the beer. If the fermentation temperature and the current beer temperature are the same life is simple.

However, if the beer was cold crashed, or put through a diacetyl rest, or the temperature changed for some other reason... you will need to use your judgment to decide which temperature is most representative. During cold crashing, some of the CO2 in the head space will go back into the beer. If you cold crashed for a very long time this may represent a significant increase in dissolved CO2. There is a lot of online debate about this and the internet is thin on concrete answers backed by research. We are open to improving the calculator so please let us know of any sources that clarify this point.

The equation this calculator uses to compute the amount of dissolved CO2:
CO2 In Beer = 3.0378 - (0.050062 * temp) + (0.00026555 * temp^2)

Update 7/2013 - The calculator now displays the volumes of dissolved CO2 in the beer prior to adding priming sugar. As the beer was fermenting it naturally retained some CO2. The amount of dissolved CO2 is temperature dependent.

Don't Over Prime!

The amount of sugar the calculator tells you to add will take the beer from the current level of CO2 to the desired level.

When bottling I typically do 3.5 ounces of corn sugar (dextrose) by weight for 5 gallons. This yields about 2.1 volumes of carbonation, which is plenty. Over carbonation leads to a lot of problems, like swollen caps, exploding bottles, and a really annoying time trying to pour foamy beer. See our article on home brew bottle bombs.

Notes on Sugars: Corn sugar and dextrose are the same thing. Dextrose is the most popular priming sugar. Table sugar can also be used, and it is assumed that corn sugar is 91% sugar, while table sugar is 100% sugar. Dry Malt Extract (DME) is another option. This calculator uses 68% attenuation for DME.

Measuring Priming Sugar: We recommend measuring priming sugar by weight. The values this calculator reports are by weight, not by volume. Weight is the most reliable method. Use the same scale you use for hop additions.

Other sources will say add X cups of sugar. The problem we have with this is, there could be air pockets inside the scoop, making it hard to tell just how much is in there. Yeah it will get you close most of the time, but it is not reliable or repeatable in comparison with measuring by weight. An under primed batch of beer is a real bummer, don't let a measuring cup be the cause.

Thanks for using our calculator. You might be interested in the Complete Recipe Builder. It is a big time saver, easy to use, and you can try it anonymously. OG/FG/IBU/SRM/ABV are automatically calculated. Recipes can be saved, printed, shared, and brewed for complete record keeping.