Enter the amount of whiskey (oz), the bottle proof, and the desired proof into the Whiskey Dilution Calculator. The calculator will evaluate the Whiskey Dilution. 

Whiskey Dilution Formula

The following formula is used to calculate the Whiskey Dilution. 

WD = (W * (BP / DP - 1))


  • WD is the Whiskey Dilution (amount of water to add (oz))
  • W is the amount of whiskey (oz) 
  • BP is the bottle proof 
  • DP is the desired proof 

How to Calculate Whiskey Dilution?

The following steps outline how to calculate the Whiskey Dilution.

  1. First, determine the amount of whiskey (oz).
  2. Next, determine the bottle proof. 
  3. Next, determine the desired proof. 
  4. Next, gather the formula from above = WD = (W * (BP / DP – 1)).
  5. Finally, calculate the Whiskey Dilution.
  6. After inserting the variables and calculating the result, check your answer with the calculator above. 

Example Problem:

Use the following variables as an example problem to test your knowledge.

amount of whiskey (oz) = 30

bottle proof = 80

desired proof = 40

WD = (W * (BP / DP – 1)) =  ?