Calculating your malt

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Jan 23, 2007
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Wichita Falls, Tx
OK, I'm doing 5 gallon batches, and will probably stick with this for the next year or so. I want to dream up my own recipes, but I'm not sure how much malt is needed for my beers. I would like them to be at least 5% ABV, no more than 6. I'm doing extract right now, but I just ordered a turkey fryer, cooler and some copper tubing so I'm about to get into AG.

1. Is there an average or something I should use for my base calculations?

2. As far as extract, is there a difference in light, dark, wheat malts when calculating how much to use?

3. As far as AG goes, is there a difference in, well, light, dark, wheat malts when calculating how much to use?


Well-Known Member
Nov 20, 2006
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1. This depends on your efficiency, and the style you're brewing. I found the book "Designing Great Beers" to be invaluable, and consult it whenever drawing up a grain & hop bill.

2. Yes, depending on the style you're brewing. Might be handy to find out what they added to your dark malt to make it darker than the light.

3. Yes, the different grains contribute different flavors, bodies, and other characteristics to your wort, and later, beer. Becoming familiar with at least the basic grains is necessary to brew the popular varieties of beer (unless you're following a pre-formulated recipe).

4. (Since you didn't ask) Different varieties of hops, added at different times, can make the same wort taste completely different. Pay attention to the hop bitterness, flavor, and aroma of the style you're brewing or would like.

5. (Since it's appropriate) Different yeast varieties will provide different characteristics for the same post-boil wort. If you were to pitch a lager yeast and London Ale yeast into identically made worts, and ferment them for the necessary times and at the proper temperatures, you would get a very different taste, feel, and finish to the beer.

It may seem overwhelming, but start small, make a pale ale or two, start getting the hang of it, and you'll get hooked on making the greatest recipe yet. Again, I'd suggest you read Designing Great Beers, after Papazian's book, if you hadn't read that.


Home brewing moogerfooger
Aug 10, 2005
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Torrance, CA
If you are going all-grain, I'll second the Designing Great Beers book. An invaluable resource.

Here's a bit of a short answer, though. Assuming you are getting 70% efficiency from your grain and an attenuation of 75% from your yeast, you will need about 10 lbs of grain for 1.050 to get 5% and 12 lbs for 1.060 to get 6%. The grains can vary depending on how much they are roasted. Generally the darker a grain is, the less fermentable sugars you get out of it.

From here you can use percentages to get you where you want. The bulk of the grain bill is a base malt. Pale Malt, Pilsner Malt, Munich Malt, Vienna Malt, Wheat Malt, Rye Malt. These are generally about 75-100% of the grain bill. Here's a few *very* simplified examples

Classic Pilsner - 100% Pilsner malt
Hefeweizen - 60% Wheat Malt/40% Pale Malt or Pilsner Malt

Then you use other "character grains" to add other flavors and colors. These can include Crystal Malts (light to dark), Chocolate Malt, Black Patent Malt, Roasted Barley, Biscuit Malt, Victory Malt, Cara Malts (cara-pils, cara-munich etc.), Aromatic Malt, Special B Malt.

Amber Ale - 85% Pale Malt, 10% Crystal Malt, 3% Biscuit Malt, 2% Chocolate Malt

Adjunct grains can also add body, mouth feel, aid head retention. Flaked Corn, Corn Grits, Oats, Flaked Barley, Flaked Wheat, Flaked Rye, Rice etc.

Classic Dry Stout - 85% Pale Malt, 10% Roasted Barley, 5% Flaked Barley

Again I would suggest reading Designing Great Beers. It has a ton of info on recipe formulation and what to use for what style and in what amount.


Well-Known Member
Dec 6, 2006
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If you are just starting AG. IMHO you would be much better off getting the 150 clone recipes from BYO or finding a clone recipe on this site to start off. Then go for your own recipe once you are comfortable with AG.


Well-Known Member
Feb 24, 2006
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My advice:

First, get to "know" grains. Do this by tasting them - literally chew on specialty grains to get a sense of what they taste like. Then, drink beers in which you know a certain grain is used. Often, microbrewery websites will reveal something about their recipe. Talk to brewers, etc. Be able to "find" a certain grain's taste in a given beer. Some are easy (black patent in porters, roast barley in stouts, etc.); others are more subtle.

Second, get a program like Promash. Use it to build beers . . . even if you never brew the beer. This will give you a sense of how much base malt yields how much ABV, etc. Get to the know the program very well.

Third, start brewing AG clones. Get the BYO clone book and use those recipes - but put them into Promash before you brew them. You will begin to see how these recipes yield the beers they do.

Finally, venture out on your own. Design a beer from a blend of a few different recipes you like. Then . . . go for it.


Well-Known Member
May 3, 2006
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Grand Junction
Since most of the comments were geared towards all-grain brewing...

For extracts, it's pretty easy to calculate and predict OG (and hence ABV). Since you don't mash your own grains, you don't have to worry about efficiency (efficiency = 1). So I first calculate Gravity Units (GU) in the wort = lbs DME * 45. (or lbs LME * 36). Then I take the total GU and divide that by the gallons of wort to obtain OG.
i.e. 5 lbs DME * 45 / 5 gallons = 45 (which corresponds to OG 1.045)
I use the value of 45 for all DME and 36 for all LME. The way they are roasted will determine color, and will carmelize some of the sugars into a non-fermentable form. There may be some small variation in this, but in general you'll be safe using the above numbers.
Then you have to find out the attenuation of your yeast (expressed in a %) to determine the efficiency of your yeast to ferment the sugars. So a 77% attenuation would be expected to ferment 77% percent roughly of the fermentable sugar (DME). So in the example above, total GU = 5*45= 225. 225 * 23% (sugar remaining after fermentation) = 51.75 GU. Then, 52 GU / 5 gallons of beer would = 10.35 (or FG of 1.010).
To calculate ABV subtract FG from OG and multiply by 131.25.
i.e. (1.045 - 1.010)*131.25 = 4.6 % ABV.
Just write down the formulas and you can "back calculate" if you have a desired alcohol level in mind and want to derive an extract bill. Just keep in mind that the higher your gravity, the less utilization of hops, and you also alter the malt:hops balance. So keep an eye on the ratio of your total gravity units to the IBU of your brew; and use a program like Promash to play around with a recipe before brew day.