How do I dilute 190 proof ethanol down to 100 proof?

Answer:
To make 1 liter of 100 proof ethanol, combine 0.53 liters of 190 proof ethanol with 0.47 liters of water. 

Mr. Tincture Says:

• 190 proof = 95% Alcohol By Volume.  100 Proof = 50% ABV.
• ​Tap water from public sources or wells is just fine for diluting 190 proof ethanol to your desired strength
• Different strengths of ethanol are useful for extracting different components of plants.
• Proof is a measurement of density of alcohol contained within the liquid

Continued Reading via the Learning Hub

• A Calculator for Diluting 190 proof Ethanol with Water​
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