Bourbon is a type of American whiskey defined by very specific legal rules: to be called “bourbon,” a whiskey has to meet all of them, not just some.

Quick Scoop

Here’s what makes bourbon bourbon :

  1. Made in the U.S.
    • Bourbon must be produced in the United States (not just Kentucky, even though Kentucky is the most famous).
  1. Mash bill: at least 51% corn
    • The grain recipe (mash bill) has to be a minimum of 51% corn.
    • The rest can be rye, wheat, and/or malted barley, which tweak the flavor.
  1. Aged in new, charred oak barrels
    • It must be aged in brand‑new oak containers that are charred on the inside.
    • No used barrels, wine casks, or refill casks if you still want to legally call it bourbon.
  1. Distillation and barrel-entry limits
    • Distilled to no more than 80% ABV (160 proof).
    • Put into the barrel at no more than 62.5% ABV (125 proof).
  1. Bottling and additives
    • Typically bottled at 40% ABV (80 proof) or higher.
    • No added flavorings or colorings are allowed—only water can be added to adjust proof.
  1. “Straight bourbon” (stricter sub‑category)
    • A “straight bourbon” must be aged at least 2 years.
    • If it’s under 4 years old, the label has to state the age.

Why it matters

Those rules are why bourbon tastes the way it does:

  • High corn gives it a sweeter, rounder profile than many other whiskies.
  • New charred oak adds that deep amber color plus vanilla, caramel, and smoky notes.

So if a bottle doesn’t tick all those boxes, it may still be whiskey—but it’s not bourbon. Information gathered from public forums or data available on the internet and portrayed here.