BeerCalc - Reference

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Detailed information about the various fields in the BeerCalc tool. If you are new to BeerCalc, see Getting Started with BeerCalc.

Volume. The amount of wort you want to have ready for fermentation at the end of the boil.

Beer Style and Style Guide. Here you choose the beer style, and the list of styles you want to be able to choose from. This may depend on your geographic location, or a competition you want to enter. The Check Style box allows you to compare your beer's vital statistics with the chosen style.

Specific Flavour. This is used to describe a style more accurately, if additional flavours are added, for example for a Fruit Beer you might want to specify which fruit was used.

Efficiency. This number is for mashed ingredients, and indicates how much sugar you extract based on a theoretical (unachievable) maximum. It varies from brewer to brewer, and can be affected by mash pH, temperature, etc. Use a value you know from experience to be realistic. When you have finished mashing and can measure your OG, you can find your efficiency by using the "Calculate Efficiency from actual OG" button. Or, just fiddle with it until the OG value is correct. Note that Efficiency does not affect how much sugar that comes from non-mashed ingredients, like malt extract, sugar or honey.

Mash schedule / mash pH. These fields are not used for calculations, they are just for information. Try and keep it short, e.g. "30 min 50C, 60 min 67C". pH is included so you can type in the measured value.

OG. Stands for Original Gravity, and is the specific gravity the wort has just before fermentation begins. Must be measured at 20C, or a compensation factor applied.

Boil Volume. If you dilute your beer after the boil, the boil volume will be different to the final volume (as per Volume field above). This means that the work will be more concentrated during the boil, which can affect how much bitterness is extracted from the hops. This field is only used if you use Tinseths hop utilization model (see below), and affects the BG.

BG. Boil Gravity. The gravity the wort has during the boil. The same as OG, unless you are going to dilute your wort after the finished boil, to get more beer from the same sized equipment. Controlled by Boil Volume.

Colour. Calculation of colour for beer (or indeed anything) is a very imprecise process, but a colour scale called EBC has been defined. (In the USA the SRM scale is used, the values are just divided by 2). There is no point in fiddling to get the last decimal in the colour value to be as you want it! The hops, the boil, your equipment - many things can affect the finished colour, and human colour perception is also variable. This is why the EBC value is translated to some vague terms, e.g. "Light Yellow". The following table is taken from Designing Great Beers by Ray Daniels.

0-5 Very pale
6+ Pale yellow
8+ Golden
12+ Amber
18+ Deep Amber / light copper
28+ Copper / reddish brown
34+ Deep copper / light brown
36+ Brown
44+ Dark brown
60+ Very dark brown
70+ Black


Hops. You need to specify which type of hops, their alpha acid content, how much and for how long they are boiled. BeerCalc calculates how much bitterness they will provide. Dry hops (added to the fermented wort) can be specified, but have no effect on bitterness. Note that each hop variety has a default alpha acid value, which you can change to fit the hops you have bought, as this varies from bag to bag.

Bitterness. Bitterness has its own scale called EBU. The higher the value, the more bitter the beer. Bitterness calculations are notoriously imprecise, and the amount of bitterness extracted from the hops will vary from brewer to brewer, due to differences in equipment and procedure.

BU:GU. This factor was introduced by Ray Daniels, and represents how bitter a beer is, in relation to its "strength". A very useful rule-of-thumb factor for getting a style right.

Yeast. Specify the type of yeast here. This is for documentation purposes only.

FG. Stands for Final Gravity, and is the specific gravity of the finished beer. Depends on the OG value, and how efficient the yeast has been in converting sugars to alcohol (attentuation). You can either type in the FG value you measure (check the "Use measured" box) or get BeerCalc to calculate an expected value, from the anticipated attenuation factor.

Attenuation. There are 3 ways to specify the attenuation:

  1. Type in the measured (or expected) FG value. To do this, check the "Use Measured" box. The attentuation will be calculated.
  2. Use the standard attenuation for the chosen yeast. To do this, check the "Use standard" box. The FG will be calculated from this.
  3. Don't check either box, and type in your own expected attenuation value. The FG will be calculated from this.

Alcohol (%vol). This is the alcoholic strength of the finished beer, calculated from the difference between the OG and the FG.

Hop util model. There are two "models" of how the hop bitterness is extracted over time, during the boil, which affects the EBU calculation. The recommended (and default) model is the Tinseth model, which takes into account the gravity of the boiling wort. This was developed by Glenn Tinseth (See his Hop Pages). The "Original" model is from an earlier BeerCalc version and is retained for backwards compatibility.

Fermentation. Information about the fermentation sequence, used for information only.

Comments. Fill these out with extra details about the process, and if any other ingredients (spices, etc) were used, so that the recipe can be recreated as accurately as possible. Other details like water treatment and so on are also interesting for readers.

Useful. To assist browsers in the recipe database it is possible to tick this box, if you (in your own opinion) have written particularly useful comments in the Comments box. This might be instructive stuff about the process, the result, or references to related recipes or brewing experiments. From the Index page, BeerCalc users can search for recipes with useful comments.

Rating. By setting the gold star (click on it) you can indicate that this is a recipe of yours that you would personally recommend to others. The star rating is visible when browsing the index. As the database contains many thousand recipes, it is useful to be able to filter out those that even the brewer would not really think are worth raving about.

Personal Info. Under the Personal Info menu you can select a number of options that affect how the tool works. For example, your normal brew volume and mash efficiency can be entered, along with options to automatically convert others recipes that you view to your parameters. You will also see a list of the homebrew competitions that are currently being managed using BeerCalc, and opt to have the entry information for these competitions displayed when you look at your recipes.

Convert Recipe to.. With these functions, you can change a recipe so it matches better to the amount of beer your normally brew, or adapt to the efficiency, you normally achieve (this affects the amount of malt used). Just press the desired function, and type in the data at the prompt. Note that a Volume change ought not to mean a significant change in OG, colour or bitterness - but they can be affected in a small way. Colour can be affected by a change of efficiency. However, as these calculations are at best very rough, this should not be important.

NaN. You may sometimes see this in some of the calculated fields. It stands for "Not A Number", and means that the value cannot be calculated given the existing input. For example, BU/GU will ne NaN if OG is 1000, as there would be a division by zero in the calculation.