The proof of moonshine is determined by the alcohol content or concentration in the final product, typically measured using a hydrometer, which measures the specific gravity of the liquid. The more alcohol in a beverage, the stronger the drink and the higher the proof. On average, a high proof moonshine could range somewhere between 100 to 150 proof. However, the actual alcohol content of a proofing moonshine depends on several factors, like temperature. Moonshine is a high-proof liquor produced illegally without government authorization, and it is called moonshine because it is traditionally illegally distilled during the night to avoid being discovered by law enforcement. It is noted for having a very high alcohol content and being distilled in a variety of handmade, ramshackle stills usually found in the woods or mountains.