Brewing Tools & Formulas

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.


Screwy's Brewing Calculators

   Alcohol Content Calculator
   American/Metric Calculator
   Batch Bottle Sizing Calculator
   Bottle Priming Calculator
   Cylinder Volume Calculator
   ezBIAB Calculator©
   ezBrewingWater-RO©
   Force Carbonation Calculator
   Grain Bill Percentage Calculator
   Hop Bitterness Calculator
   Hop Bitterness, Flavor And Aroma Chart
   Hop Bitterness Balance Calculator
   Mash Water Volume Calculator
   Rest Temperature Calculator
   Standard Reference Method Color Chart
   Strike Temperature Calculator


qBrew - Homebrewers Recipe Calculator

  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.
Download it today and also get Screwy's database including the latest Mr. Beer ingredients.

   qBrew - Homebrewers Recipe Calculator

Alcohol Content   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.

 

Alcohol Content Calculator
Enter your original and final hydrometer readings below, then click 'Calculate'
Original Gravity (OG)			SG °Plato
Final Gravity (FG)
Real
Apparent attenuation			ABW
Real attenuation			ABV
Freezing point		degrees	°F °C
Calorie content for	mL L hL oz cups pt qt ltr gal bbl Imp oz Imp pt Imp qt Imp gal Imp bbl	=		calories
Forced Carbonation Calculator
Using the 'set and forget' method of forced carbonation is the easiest and most accurate way to force carbonate kegged beer. Simply hold the temperature of your beer constant (34-38°F) then set your CO2 regulator pressure and gas your beer for a week. This will give you the consistent carbonation levels that are necessary for balancing your draft lines and taps to produce great pours.
Enter the temperature of the beer to carbonate and your target Co2 volume.
Temperature of beer [°F]
Target CO2 volumes
Regulator pressure [psi]
Bottle Priming Calculator
Naturally carbonating your beer should be done soon after your beer has reached it's final gravity, which is based on getting the same hydrometer reading two or more days apart. Adding the right amount of fermentable sugar to the beer will provide the yeast with just enough food for them to create the right amount of CO2 needed to hit your carbonation level. Remember when using the calculator be sure to input the 'warmest' temperature the beer has reached prior to bottling it, colder beer holds CO2 in solution better than warmer beer which allows CO2 to escape easier.
Enter your target CO2 volume, beer temperature, beer volume and priming ingredient.
Desired CO2 volumes
Beer temperature		degrees	°F°C
Beer volume			mL L hL oz cups pt qt ltr gal bbl Imp oz Imp pt Imp qt Imp gal Imp bbl
Priming ingredient	Corn sugar (glucose/dextrose) Cane sugar (sucrose) Honey (84% AA) Dried malt extract (55% AA) Dried malt extract (70% AA) Dried malt extract (75% AA)
Residual CO2		volumes
Sugar needed		tsp tbsp oz lb g kg

** A reference temperature of 0°C is used to measure the volume of CO2 **

This information is provided 'as is', the author assumes no liability for the use of the results
from this calculator. Always take care when entering data and/or using the results of your calculations.


Beer Carbonation Guide By Style

ALES
Styles	CO2 Volumes
Barley Wine
Barley Wine	1.3 to 2.3
Belgian Specialty
Flanders Brown	1.9 to 2.5
Dubbel	1.3 to 2.3
Trippel	1.9 to 2.4
Belgian Ale	1.9 to 2.5
Belgian Strong Ale	1.9 to 2.5
White	2.1 to 2.6
Lambic Gueuze	3.0 to 4.5
Lambic Faro
Lambic Fruit	2.6 to 4.5
English Bitter
English Ordinary	0.75 to 1.3
English Special	0.75 to 1.3
English Extra Special	0.75 to 1.3
Scottish Ale
Scottish Light	0.75 to 1.3
Scottish Heavy	0.75 to 1.3
Scottish Export	0.75 to 1.3
Pale Ale
Classic English Pale Ale	1.5 to 2.3
India Pale Ale	1.5 to 2.3
American Style Pale Ale	2.26 to 2.78
English & Scottish Strong Ale
English Old Ale/Strong Ale	1.5 to 2.3
Strong Scotch Ale	1.5 to 2.3
Brown Ale
English Brown Ale	1.5 to 2.3
English Mild Ale	1.3 to 2.0
American Brown Ale	1.5 to 2.5
Porter
Robust Porter	1.8 to 2.5
Brown Porter	1.7 to 2.5
Stout
Classic Dry Irish	1.6 to 2.0
Foreign Style	2.3 to 2.6
Sweet Stout	2.0 to 2.4
Imperial Stout	1.5 tp 2.3
LAGERS
Bock
Traditional German Dark	2.2 to 2.7
Helles Bock	2.16 to 2.73
Doppelbock	2.26 to 2.62
Eisbock	2.37
Bavarian Dark
Munich Dunkel	2.21 to 2.66
Schwarzbier	2.2 to 2.6
American Dark
American Dark	2.5 to 2.7
Dortmund/Export
Dortmund/Export	2.57
Munich Helles
Munich Helles	2.26 to 2.68
Classic Pilsener
German Pilsener	2.52
Bohemian Pilsener	2.3 to 2.5
American Light Lager
Diet/"Lite"	2.57
American Standard	2.57
American Premium	2.57 to 2.73
Dry	2.6 to 2.7
Vienna/Oktoberfest/Marzen
Vienna	2.4 to 2.6
Oktoberfest/Marzen	2.57 to 2.73
MIXED STYLE
German Ale
Dusseldorf-style Altbier	2.16 to 3.09
Kolsch	2.42 to 2.73
Cream Ale
Cream Ale	2.6 to 2.7
American Wheat
American Wheat Beer	2.3 to 2.6
Smoked Beer
Bamberg-style Rauchbier	2.16 to 2.57
California Common
California Common Beer	2.4 to 2.8
German Wheat Beer
Berliner Weisse	3.45
German-style Weizen (Weissbier)	3.6 to 4.48
German-style Dunkelweizen	3.6 to 4.48
German-style Weizenbock	3.71 to 4.74

Batch Bottle Sizing Calculator

Use this calculator to figure out how to bottle beer in the exact combination you desire.

A 5 gallon batch of beer fills up:

• 54 - 12 ounce long necks
• 38 - 16.9 ounce half liters
• 30 - 22 ounce bombers
• 10 - 64 ounce growlers
• 4 - 5 liter mini kegs

Units:	US - Gallons / Ounces Metric - Liters / Milliliters
Gallons to package:
Ounces to package:
Liters to package:
Milliliters to package:
	Units	Quantity	Amount Bottled
Euro 330ml	11.2 oz 330 ml
Long Neck	12 oz 355 ml
Grolsh	15.2 oz 450 ml
Half Liter	16.9 oz 500 ml
Bomber	22 oz 650 ml
Wine	25.4 oz 750 ml
Grenade	32 oz 946 ml
Growler	64 oz 1893 ml
Gallon Jug	128 oz 3785 ml
5 Liter Mini-Keg	169 oz 5000 ml
		Bottled:
		Batch Size:
		Remaining:

Enter your hop additions on separate lines including.....

Wort gravity, Volume, Alpha Acid, Ounces and Boil Time then click 'Calculate'.


HOP Bitterness Calculator
** For Mr. Beer HME enter an SG of 1.036, 1.0 Ounce and a Boil Time of 5 minutes. **

Wort Specific Gravity (during boil)

Final Volume (gal)

Addition	Alpha Acid %	Oz. Added	Boil Mins.	Utilization %	IBUs
First
Second
Third
Fourth
Fifth
				Total IBUs

 

Mr. Beer Hopped Malt Extract (HME) Hop Guide
Mr. Beer (HME) Example Input: SG = 1.036 - 1 Oz. - 5 Minute Boil
Hopped Malt Extract	Alpha Acid %
American Devil IPA	16.3
Bewitched Red Ale	7
Black Tower Porter	5.7
Classic American Blonde	10.2
Cowboy Golden Lager	10.2
Englishman's Nut-Brown Ale	12.4
Grand Bohemian Czech Pilsner	5.1
High Country Canadian Draft	12.4
Linebacker Bock	12.4
Octoberfest Vienna Lager	13.1
Pilothouse Pilsner	5.1
St. Patrick's Irish Stout	18.1
Sticky Wicket Oatmeal Stout	8
West Coast Pale Ale	12.4
Whispering Wheat Weizenbier	10.2
Witty Monk Witbier	5.1

Bitterness Balance Calculator

The BJCP Style Guidelines state the desired number of International Bittering Units (IBU) that are needed to obtain a balance between hopped bitterness and malt sweetness in a hopped beer style. Beers that don't taste sweet or bitter are considered to be balanced, although individual beer drinkers may percieve this differently. The formula used in this calculator returns the desired IBUs needed to keep a hopped beer style in balance using the formulas published on the Beer Color and Brewer's Math website. The formula takes into consideration the beer's original gravity, actual attenuation and bittering level but does not take into account phenol, ester or other complexities. The beer drinker should use the desired IBUs as a reference point and decide for themselves what they consider to be balanced.
Original Gravity		BJCP Style Guidelines
Apparent Attenuation	65%66%67%68%69%70%71%72%73%74%75%76%77%78%79%80%	1A. Lite American Lager1B. Standard American Lager1C. Premium American Lager1D. Munich Helles1E. Dortmunder Export2A. German Pilsner (Pils)2B. Bohemian Pilsener2C. Classic American Pilsner3A. Vienna Lager3B. Oktoberfest/Märzen4A. Dark American Lager4B. Munich Dunkel4C. Schwarzbier5A. Maibock/Helles Bock 5B. Traditional Bock5C. Doppelbock5D. Eisbock6A. Cream Ale6B. Blonde Ale6C. Kölsch6D. American Wheat or Rye Beer7A. North German Altbier7B. California Common Beer7C. Düsseldorf Altbier8A. Standard/Ordinary Bitter8B. Special/Best/Premium Bitter8C. Extra Special/Strong Bitter (EPA)9A. Scottish Light 60/- 9B. Scottish Heavy 70/-9C. Scottish Export 80/-9D. Irish Red Ale9E. Strong Scotch Ale10A. American Pale Ale10B. American Amber Ale10C. American Brown Ale11A. Mild11B. Southern English Brown Ale11C. Northern English Brown Ale12A. Brown Porter12B. Robust Porter12C. Baltic Porter13A. Dry Stout13B. Sweet Stout13C. Oatmeal Stout 13D. Foreign Extra Stout13E. American Stout13F. Imperial Stout14A. English IPA14B. American IPA14C. Imperial IPA15A. Weizen/Weissbier15B. Dunkelweizen15C. Weizenbock15D. Roggenbier (German Rye Beer)16A. Witbier16B. Belgian Pale Ale16C. Saison16D. Bière de Garde17A. Berliner Weisse17B. Flanders Red Ale 17C. Flanders Brown Ale/Oud Bruin17D. Straight (Unblended) Lambic17E. Gueuze17F. Fruit Lambic18A. Belgian Blond Ale18B. Belgian Dubbel18C. Belgian Tripel18D. Belgian Golden Strong Ale18E. Belgian Dark Strong Ale19A. Old Ale19B. English Barleywine19C. American Barleywine22A. Classic Rauchbier
		International Bittering Units (IBU)

Mash Calculators

Mash temperatures play a significant role in the creation of your wort and the beer that is made from it. Many brewing publications agree that the optimum temperature range for an infusion mash ranges from 147°F to 155°F. A mash done at the lower end of this range will produce a well attenuated lower gravity beer and a mash done at the higher end of the range will produce a dextrinous higher gravity beer.

It is important to hit your required mash temperature as early as possible when adding your hot water to the grains. Within the first 5 minutes of the mash is when the enzymes are the most active and when they will produce the most fermentable sugars. Needless to say if you unintentionally go in too hot with your strike water you will overshoot your final gravity so it's important to heat your strike water correctly at the very start of the mash.

The formulas used in the calculators below are based on the earlier work of Ken Schwartz as published on Green Bay Rackers and have been modified for use on this site. The calculators have been tested but you should note that they are meant to provide you with approximate recommendations as they do not take into account differences in your equiptment or brewing process. Use care when entering your input data, avoid typos as the calculators will crunch them as well as correct input data.

To get the most from your calculations use the output values as a starting point and be sure to write down your actual results as they pertain to your brewing equipment. Using your notes as a reference when calculating your next mash will help you fine tune differences in the surface area, volume, temperature and heat loss of your current equiptment.

Strike Temperature Calculator

To calculate the Required Strike Temperature you will need to heat your water to in order to hit your Target Strike Temperature enter the following information.  First enter your Mash Thickness, the ratio of sparge water to used in the mash. (Example: 1.25 qts. water to 1 lb. grain)  Next enter your Target Strike Temperature, the mash temperature you wish to maintain inside your mash tun. (Example: 153 F)  Then enter the Grain Temperature, the temperature of the grains inside your mash tun before adding any water. (Example: 70 F)
Mash Thickness		Qt/Lb or L/kg
Target Strike Temperature		Degrees
Grain Temperature		Degrees
Required Strike Temperature		Degrees
Units of Measurement:	American	Metric

Rest Calculator

To calculate the Amount Of Boiling Water you will need to raise your mash water to in order to hit your Target Strike Temperature enter the following information.  First enter your Weight of Grains, the dry wieght of the grains in the tun. (Example: 10 lbs. grain)  First enter your Mash Thickness, the ratio of sparge water to used in the mash. (Example: 1.25 qts. water to 1 lb. grain)  Next enter your Current Mash Temperature, the mash temperature you wish to maintain inside your mash tun. (Example: 135 F)  Next enter your Target Strike Temperature, the mash temperature you wish to maintain inside your mash tun. (Example: 153 F)  Then enter the Grain Temperature, the temperature of the grains inside your mash tun before adding any water. (Example: 70 F)
Weight of Grains		Lb or kg
Mash Thickness		Qt/Lb or L/kg
Current Mash Temperature		Degrees
Target Strike Temperature		Degrees
Amount Of Boiling Water		Qts or Liters
Units of Measurement:	American	Metric

Mash Water Volume Calculator

To calculate the Amount Of Space your mash will require, including grains and water, enter the following information.  First enter your Weight of Grains, the dry wieght of the grains in the tun. (Example: 10 lbs. grain)  First enter your Mash Thickness, the ratio of sparge water to used in the mash. (Example: 1.25 qts. water to 1 lb. grain)
Weight of Grains		Lb or kg
Mash Thickness		Qt/Lb or L/kg
Amount Of Space		Gallons or Liters
Units of Measurement:	American Metric

Calculate The Percentage Of Grains

Enter the Percentage of grains, in pounds, ounces or grams, to calculate the total weight.
The default weight of 10 pounds of grains is used in the example below.

No. Grain Bill Percentage Unit Amount 1 % lb 2 % lb 3 % lb 4 % lb 5 % lb TOTAL: 0.00% 0.000 Size Unit: PoundsOuncesGrams