Calculate Cells Needed, DME, Yeast Viability and Starter Size for your homebrew
The goal of this tool is to help you calculate the amount of starter that you need to prepare when pitching liquid yeast to your homebrew.
This is done by firstly calculating the amount of Yeast Cells Needed to ferment your homebrew based on its Original Gravity and Batch Size.
After that you need to calculate the Viable Cells of your yeast, using its production date or by punching in the Viability%. This gives you an estimation of the Viable Cells in your Yeast. If the Viable Cells Count is less than the Yeast Cells Needed, then you need to make a starter.
To make a starter you need to select the Method of Aeration first. Here you indicate if you are using a Stir Plate, you are Manually Shaking the starter or None. There are 2 kind of formulas, those of Chris White and Jamil Zainasheff derived from their book "Yeast", and those of Kai Troester derived from his study on Yeast Starters. After you select your Method of Aeration, your Yeast Starter Volume and Gravity of Starter, the Total Yeast Cells of the Starter are calculated based on the Viable Cells of your Yeast(from the previous step).
If the Total Cells at Finish are still less than the Yeast Cells Needed, you can make a Second or even Third Starter(Step Up), using the Step 2 and Step 3. Each Step takes as an input the output of the previous Step.