Screwy Calc(at right) uses the Original Gravity (OG) and Final Gravity (FG) temperatures to calculate the residual CO2 volumes of your beer.
Specific gravity temperature corrections are also applied to calculations of calories, carbohydrates, attentuation, extract, Plato and yeast pitching rates.
Yeast pitching rates are calculated in billons of cells. The formula uses adjusted final gravity Plato and wort size in gallons to determine how much yeast should pitched for either Ale and Lager type beers.
This free beer recipe calculator is intuitive, easy to install and fun to use.
Use it to automatically calculate the gravity, color and bitterness of your own recipes.
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Enter the full specific gravity (SG) readings including the decimal point and the percentage of alcohol will be calculated when you click on the submit button.
(Example:1.050)
(OG) - Original Gravity
The first reading is of the beer in your fermenter, before you start the fermentation process. Take this reading when all the water has been added and you are ready to pitch the yeast. Pour a sample out of the tap into a test flask and set it aside to cool to about 70F (20C).
(FG) - Final Gravity
The second reading is of the finished beer. This is taken when you are ready to bottle your beer and this too should be about 70F (20C).
Residual CO2
A certain amount of Residual CO2 remains in the beer after the fermentation has completed, depending on the fermentation temperature. An ale fermented at 65°F will have 0.9 volumes of residual CO2 while a lager fermented at 50°F will have 1.2 volumes. To get the same carbonation in these two beers would require different amounts of priming sugar.
Too much priming sugar or bottling a batch of beer that is not done fermenting can cause exploding bottles so don't carbonate bottles to higher pressures than the beer that came in them and exercise caution when entering numbers and using the results from this calculator.
Please note that DME varies in its fermentability, a few example brand names are provided with their approximate apparent attenuation (AA) values. Typically, DME has an AA of 70% to 75%, with the notable exception of Laaglander brand at 55%
The apparent attenuation you will get on a given batch depends on a number of factors, including the types of grains/extracts used, mash temperature (if brewing all-grain), and the strain of yeast. Typically, apparent attenuation will range from 65 to 80%. Beers with a lower apparent attenuation will be sweeter, fuller-bodied, and lower in alcohol. Higher apparent attenuation will result in a drier, thinner, higher alcohol brew.
Brew In A Bag Calc
(Example: A 220 volt 5,000 watt heating element times 3.412 converts to 18,766 btus per hour.)
Calculate The Volume Of A Cylinder
Enter the Radius and Height of the cylinder, in feet or inches, to calculate it's volume. The volume of a hydrometer tube 10 inches tall and 1 inch in diameter is calculated below.
American/Metric Conversion
TheStandard Reference Method or SRM Color Chart
Note that SRM is a measure of beer color density more than hue/tint. Keep this in mind when attempting to use only SRM numbers when describing beers. Within these Guidelines, beer color descriptors generally follow this mapping to SRM values.
Hop Bitterness, Flavor, Aroma Chart
Boiling hops for more than 60 minutes doesn't contribute much more bitterness since most of the hop oil isomerization happens earlier in the boil . Maximize hop flavor by boiling them for no more than 20 minutes and to get the most hop aroma boil them for 7 minutes or less. Additional ways of increasing hop aroma is to add them at the very end of the boil and leave them in the kettle as the wort cools. You can also add aroma hops to the fermentor about 4 days after pitching your yeast or 14 days before bottling or kegging.
