Problems with the calculator
The calculator requires the Adobe Flash player. It can be downloaded for free from:
http://www.adobe.com/shockwave/download/download.cgi?P1_Prod_Version=ShockwaveFlash&promoid=BIOW
There are players available for many platforms and browsers. Some folks report better success with Microsoft's Internet Explorer and others with the free Mozilla FireFox browser. If you run into trouble using this calculator, it is usually an issue with the Flash player running for a long time (several hours). Often closing the browser and starting fresh is all it takes to resolve the issue.
When you first open the calculator, you'll see the intro screen. Go ahead and read it, and then click ok.
The tabs located near the top of the calculator select which type of yeast numbers are displayed. If you haven't set up your preferences yet, this is a good time to do it. This way you'll get the information in the units that will help you the most. The rest depends on what form of yeast you will use. If you are using dry yeast, click the "Dry Yeast" tab. If you are using White Labs or Wyeast liquid yeast use the "Liquid Yeast" tab. If you are pitching from a previous yeast slurry, select the "Repitching from Slurry" tab.
This sample calculation will be done from the liquid yeast tab. In this tab we are trying to figure out either how many liquid yeast packets we will need to pitch or how big of a starter we will make.
Fermentation Type
The fermentation drop down menu allows you can choose if you are brewing and ale, lager or hybrid. A hybrid is either an ale fermented at lager temps or a lager fermented at ale temps. Go ahead and select the fermentation type for the beer you plan to brew.
Specific Gravity
Now enter the specific gravity of the beer that you plan on brewing. This number will be in O.G. or Plato depending on your selection from the preferences menu.
Volume
Next you will enter the volume of beer that you plan on brewing. The units of measure will vary depending on your selection from the preferences menu.
Viability
Viability is a measure of yeast health. You can de-select the viability checkbox and enter your own number in manually, but this is a number that you probably won't know.
It is best to go by the date your yeast was produced otherwise known as the production date. This should labeled on your package of yeast. When using Wyeast packs, the date on the package is the production date and can be entered directly. When using White Labs vials, the date on the vial is a 'best by' date and the production date is 4 months prior to that for ale and lager yeasts (6 months for brett and bacteria products). Either enter the production date in the field or click the small calendar to the right of the date, to bring up a calendar that you can select the date from.
Yeast viability depends a lot on how it is handled and it can drop off very rapidly. Shipping yeast tends to zap a lot from liquid yeast cultures, especially during hot weather. While the liquid yeast companies work miracles with their products, yeast end up using their reserves to cope with no food and hot temperatures. Some folks say that they've used a yeast package that was a year or more past its due date, which is certainly possible. However, you'll generally want to stick with the viability as it is calculated and always make a starter.
Calculate
The calculator in most cases updates the fields as you enter your parameters. If it hasn't, you can click the Calculate button to have the numbers recalculated.
Now, with everything entered, you have the yeast numbers for properly fermenting your beer. If you want to see the differences in how much yeast would be needed using dry yeast or repitching yeast, you can click on the other tabs.
Calculation Numbers from Dry Yeast
Calculation Numbers from Liquid Yeast
Calculation Numbers from Repitching Slurry
