The baseball bat is a club-like "tool" used in the sport of baseball. The MLB regulations for a baseball bat are 2.75 inch diameter and a maximum length of 42 inches. Most bats sized for adult players are around the 33 inch (sic!) mark, give or take an inch, sometimes in fractional increments. Bats traditionally are crafted to weigh the same amount in ounces they measure in inches, leaving an adjustment of three ounces to the intended user's preference, the difference being called "bat drop". Theoretically, "corking" or hollowing out part of the barrel and replacing the removed material with less dense one can improve the speed on the swing, but for example American Major League forbids this practice entirely. In high school leagues and Little Leagues, bats are made of aluminum or other metals because of the lethality of a broken bat flying at a player or the audience. The bat is intended to be used in baseball and not as a weapon. However, the baseball bat has become a staple weapon for mobsters and rioters. It is a simple bludgeoning weapon that can inflict pain, shatter bones, and kill.

In nations were Baseball is not so well known and bats are more thought as weapons, you need a license to own a baseball bat.